⚠️ WARNING: Tor VPN is beta software. Do not rely on it for anything other than testing. It may leak information and should not be relied on for anything sensitive.
Understand the basics of Tor VPN.
Features of Tor VPN.
Understand how to circumvent internet censorship with Tor VPN
Troubleshoot common issues and ways to contact support when encountering issues
Security features and properties of Tor VPN
Understand the basics of Tor VPN.
Tor VPN is a Tor-powered app which routes other apps on users' device through the Tor Network. Tor VPN benefits from the privacy features of using Tor, hides your real IP address and protects you against surveillance and censorship.
⚠️ WARNING: Tor VPN is beta software. Do not rely on it for anything other than testing. It may leak information and should not be relied on for anything sensitive.
The Tor network can be understood as a network of virtual tunnels that allows you to improve your privacy and security on the Internet. Tor works by sending your traffic through three random servers (also known as relays) in the Tor network. The last relay in the circuit (the "exit relay") then sends the traffic out onto the public Internet. Using the Tor network, makes it difficult to track a user's internet activity by preventing any single point on the network from being able to view both where the traffic originated from and where it is ultimately going to. It conceals the destination of the traffic (i.e. names and addresses of websites you visit) from your Internet Service Provider (ISP) and anyone watching your connection locally and the operators of the websites and services that you access and anyone watching them will see a connection coming from the Tor network instead of your real Internet (IP) address.
Tor VPN, a free and open source software developed by the Tor Project, is a Tor-powered app which can be used to route other apps on users' device through the Tor network. Tor VPN leverages the use of the Tor network routing the traffic through relays in the Tor network. Some major uses and advantages of using Tor VPN:
Tor VPN is only available on Android.
Tor VPN is free software. Free, both as in libre software, and, available free of charge. To make sure you are installing the correct Tor VPN, please only download from the official sources as mentioned below.
Tor VPN is only available for the Android operating system and requires:
Android Tablets and Chromebooks are not supported.
Tor VPN can be downloaded and installed from the Google Play Store.
Tor VPN can be downloaded and installed from F-Droid.
Once installed, you can launch Tor VPN from the Play Store by clicking on "Open" or from the list of applications installed on your phone. On the "Connect" screen, by default, all applications installed on the phone are configured to route through Tor VPN with the option "All apps protected" toggled on.
Screen sequence from first launch to Tor VPN connection established
You can configure Tor VPN to connect to the Tor network automatically with the previously saved connection settings, every time the app is launched.
Configuring Tor VPN to connect automatically on every launch.
Tor VPN must be kept updated at all times. If you continue to use an outdated version of the software, you may be vulnerable to serious security vulnerabilities that can compromise your privacy and anonymity.
You can update Tor VPN from the app stores.
Tor VPN can be uninstalled directly from Google Play Store, F-Droid or from your mobile device's application settings.
Features of Tor VPN.
By default all applications installed on your phone are configured to route through Tor VPN, except any of the Tor powered apps, like the Tor Browser for Android and Orbot.
It is also possible to permit only certain apps to use Tor VPN and route them through the Tor network.
Configuring applications to use Tor VPN
Exit relay is the final hop in each of your Tor circuits. You can configure Tor VPN to only choose exit relays from one particular country.
When connecting with the Tor network, websites and apps will think you are connecting from the same country as your Tor exit relay.
To configure the exit location of the Tor connections:
Configure exit location of the Tor connections
The 'Kill switch' can be used to block apps from connecting to the internet if the Tor network cannot be reached.
To activate the 'Kill switch':
Configure how the Tor VPN app appears on your phone.
To change the appearance of the App icon and name of the application:
Configuring the how Tor VPN appears on your device.
Understand how to circumvent internet censorship with Tor VPN
Direct access to the Tor network may sometimes be blocked. When this happens, Tor VPN can be used with censorship circumvention tools known as Bridges.
After exhausting common troubleshooting steps, if Tor VPN fails to initiate a connection to the Tor network, it is possible that your connection to Tor is censored. In that case, connecting with one of the built-in censorship circumvention methods might help.
Tor VPN supports the following types of bridges:
Depending on where you are, one type of bridge may work better than the other.
If using the built-in, obfs4 and Snowflake, censorship circumvention methods do not work, you will have to request other bridges. Since bridge addresses are not public, you will need to request them yourself directly from the app:
If you have obtained bridges via Email or the Bridges website, you will have to manually add the bridges.
Configure Tor VPN to use bridges
Troubleshoot common issues and ways to contact support when encountering issues
Troubleshooting common errors when running Tor VPN.
If Tor VPN is unable to connect, you might see a error message:
Connection Error on Tor VPN.
To troubleshoot, try each of the following:
Taking a look at the Tor VPN logs can be helpful in diagnosing the issue. To fetch the Tor VPN logs:
00:00:00:00 W/onionmasq: onion_tunnel::runtime: Arti failed to connect to [2a00:ccc1:1:2c::1]:9000: Network is unreachable (os error 101)
00:00:00:00 W/onionmasq: tor_chanmgr::transport::default: Connection to [scrubbed] failed: error: Network is unreachable (os error 101)
00:00:00:000 E/onionmasq: onionmasq_mobile::ffi: runProxy() returned error: couldn't start onionmasq proxy
00:00:00:000 CONNECTION_ERROR
00:00:00:000 D/onionmasq: onionmasq_mobile: closing proxy...
In this case, trying one of the censorship circumvention methods might work.
How to contact support, report a bug or give feedback.
If you encounter an issue that's not answered by our documentation, please try the Troubleshooting steps. If that does not work, please file a bug report or contact our support team.
When sending us a support request, feedback or reporting a bug, please include as much information possible:
On Tor Forum, create an account to submit a new topic. Please review our discussion guidelines and check the existing topics before posting.
If reporting a bug, please report it on our bug tracker. Please check if the bug has already been reported. To search and view all bug reports related to Tor VPN, please navigate to the Tor VPN repository.
To create a new bug report, please request a new account to access Tor Project's GitLab instance. File the bug report in the Tor VPN repository.
Send us a message on @TorProjectSupportBot.
Send us an email to frontdesk@torproject.org
In the subject line of your email, please tell us what you are reporting. The more specific your subject line is, the easier it will be for us to understand and follow up. Sometimes when we receive emails without subject lines, they're marked as spam.
Send us a message on +447421000612.
Send us a message on +17787431312.
Security features and properties of Tor VPN
This document provides insights into the security characteristics of Tor VPN, describes the nature of the benefits that Tor VPN provides and when they apply. The intended audience for this threat model document includes developers, UX designers, documentation writers, technical trainers, and technical users.
August 6, 2025
Similar to Tor Browser, and unlike traditional VPNs, Tor VPN gives each application its own route through the Tor network. This feature prevents network adversaries from linking a user's private activity with their non-private activity.
In contrast to Tor Browser, the privacy benefits that Tor VPN provides depend highly upon the behavior of individual applications, the permissions granted to those applications, and the configuration of the base Android system.
For privacy-hostile applications in partial Tor mode, or for applications that users only occasionally use with Tor, Tor VPN provides only censorship circumvention and protection from network surveillance.
When used on properly configured privacy-enhanced Android distributions such as GrapheneOS, Tor VPN can provide additional privacy benefits even for privacy-hostile applications.
This document describes the nature of the benefits that Tor VPN provides and when they apply.
The Tor VPN threat model uses the ICTM methodology. ICTM specifies security invariants that the user can expect when using the software in a particular way or in a particular environment. An ICTM threat model starts from a point of "No Security" and adds security invariants when the software environment meets particular requirements.
We express what Tor VPN provides in terms of ICTM security invariants, which apply to specific application types and usage scenarios.
In our usage of ICTM, we define five ICTM security invariants that represent levels of privacy that Tor VPN provides. This document links these invariant terms in Capitalized Bold Italic to their definition sections.
These security invariants apply to the combination of four types of Android applications, two modes of Tor VPN (all-app or per-app), and five Android device configurations. This document links these classification terms in Capitalized Bold to their definition sections.
The combined outcome results in two threat model matrices that represent the ICTM security invariant that is active in a given situation.
The level of pseudonymity that Tor VPN provides to the user guides the overall threat model.
Tor VPN provides at least censorship circumvention to all selected apps.
Tor VPN does not magically make all apps anonymous or pseudonymous. If the user used their real name or even created their account without Tor, then they have no pseudonymity.
If the user uses a privacy-enhanced version of Android and is careful about their Google account setup and app usage, then Tor VPN can help protect the usage of a single pseudonym for the user of the device. (The user may try to use different names in different apps, but app behavior can link these pseudonyms to the Google account and/or to each other).
If the user uses privacy-preserving apps with proper configuration, then Tor VPN can enable the usage of separate pseudonyms in those apps. (When properly configured, an adversary cannot link the different pseudonyms used in distinct privacy-preserving apps).
Essentially, this threat model describes the circumstances under which the user obtains these different levels of pseudonymity protection.
The low-level VPN security properties and the ICTM security invariants support the Tor VPN threat model.
Two low-level security properties that the OnionMasq networking daemon provides support the ICTM security invariants. These low-level security properties must hold for the ICTM invariants to apply:
Network Leak Safety. Apps MUST NOT be able to bypass the VPN when it is enabled. This includes during device startup, if the VPN is not connected yet, or if the network is temporarily disconnected. The VPN industry calls this property a "Kill Switch", "Always On VPN Lockdown", or "On Demand". The Always-on Lockdown feature of Android 8 and above provides this property.
Network App Isolation. All network activity of each Tor-routed app MUST be isolated from other apps by using its own dedicated Tor circuit(s). Specific apps MAY bypass Tor entirely if the user chooses to allow this. The ConnectivityManager APIs of Android 10 and above provide this property.
These are the security invariants that Tor VPN is capable of providing to individual apps. To simplify activation conditions, some invariants inherit the properties of earlier ones. We list these inherited invariants under each invariant.
The high-level conceptualization to keep in mind is that we are defining distinctions in the level of pseudonymity that the user can expect for an app: no pseudonymity, multi-app shared pseudonymity, per-app pseudonymity, and anonymity.
The next section lists the activation conditions under which they apply.
NOTE: Linkable Pseudonymity is a fragile state. As pseudonymous activity is linked together, the odds increase that there is some way to deanonymize some of that activity, thus deanonymizing all of it. One can conceptualize this invariant as providing "Multi-App Shared Pseudonymity," where all apps with Linkable Pseudonymity on the device effectively share the same pseudonym. This is why we require either the Pseudonymous Google Configuration or Google-Free Configuration for apps to gain this invariant. (Pseudonymity would otherwise vanish as soon as it was linked to a non-pseudonymous Google account.)
NOTE: One can conceptualize this invariant as providing "Per-App Pseudonymity." Because of Tor VPN's Network App Isolation, when this invariant is active for an app, its activity cannot be linked to non-private activity on the device. This is not the case for traditional VPNs, which allow the VPN operator and VPN endpoint observers to link such activity.
Our security invariants activate depending on what type of app is in use, the Tor VPN mode (per-app or all-apps), and properties of the base OS and configuration.
The lowest numbered invariant where an app matches these clauses is the invariant for that app.
A device may have multiple apps operating at different security invariant levels, depending on these conditions.
The Threat Model Matrices present this same activation information in table form.
Rationale: Surprisingly, this is a common failure mode for VPN apps among people who do not understand how they work.
Rationale: We cannot provide any additional security to a device that is already vulnerable to unfixed, publicly disclosed security flaws. We assume these public flaws can subvert any privacy or security properties the user would hope to gain by running Tor VPN.
Rationale: In per-app mode, apps that are not selected for Tor use get no protection. (Though they could if we implemented a per-app network block feature).
Rationale: Privacy-hostile applications can trick the user into opening URLs in apps that are not selected to use Tor and can link non-Tor activity to their activity.
Rationale: On all versions of Android, Privacy-hostile applications can use the
ACCESS_NETWORK_STATEAndroid permission to determine the SIM card IP address and can engage in data sharing with the ISP, which removes Network Privacy. On Stock Google Android (but not GrapheneOS), they can bind to the cell network interface to directly bypass the VPN for arbitrary network connections.
Rationale: We assume unmasked apps have no pseudonymity.
Rationale: Privacy-hostile apps can link their activity to the user's real name and Google account unless the user takes further steps.
Rationale: Pseudonym-friendly apps can be accidentally linked to a user's real name and Google account through push notifications, phone number authentication, and other mechanisms, unless the user takes further steps.
Rationale: The usage of Google push notifications links the pseudonymous app to the device's Google account, which is also pseudonymous in this configuration.
Rationale: Privacy-hostile apps can cooperate with other privacy-hostile apps on the phone to link activity, even without a device Google account.
Rationale: These device configurations prevent linkability of the pseudonymous app to the device's Google account.
Rationale: This device configuration isolates privacy-hostile apps from the device's Google account and from each other.
Rationale: Anonymity apps have no other identifiers other than the current IP address, which is now a Tor exit IP address.
As can be seen, our security invariants depend upon the app type and the Android device configuration. In this section, we define those applications and configurations specifically.
We classify Android applications into four types:
NOTE: Once an app is unmasked on a device, creating a new pseudonymous account in the same app does not remove this classification. In fact, due to the Android ID identifier behavior, deleting the app and reinstalling it in the same profile still allows a new pseudonym to be linked to the deleted one. A user must use the Isolated User Profile Configuration to create a new device user profile to use the app in an unlinkable way with respect to the current profile's Android ID for that app.
- Examples of unmasked usage include:
- Signal registered with a regular phone number.
- A ProtonMail account accessed over non-Tor.
- An Element account linked to an email address in the user's real name.
- Any app that has been linked with a non-pseudonymous Google account (via push notifications, location usage, etc.).
- Any app that has been linked to a pseudonymous Google account that is later accessed over non-Tor.
Architecturally, Tor VPN is capable of providing a high degree of unlinkability to applications on the same device, as we can see from the security invariants. Unfortunately, Android is an extremely privacy-invasive platform. The Android ecosystem has been built upon the same advertising model that the web has been built upon. Because Google controls Android and is the primary benefactor (if not sole conduit) of Android advertising revenue, Google designed the platform to maximize the ability to track usage and to link user activity together to build a comprehensive advertising profile of the user. This linkability is problematic even for apps that provide pseudonymity as a design goal, merely through their usage of the system APIs. The primary way that the system subverts pseudonymity is by associating the pseudonym with the Google account, most often through push notifications, but also through associating location information with the Android Advertising ID. On a stock Google Android, the device's Google account gets full device information: serial number, IMEI, IMSI, phone number, WiFi MAC address, full location history, and installed application list. We assume that any linking mechanism to the stock Android Google account provides deanonymization of a pseudonym. In these cases, apps can gain Network Privacy at most. The good news is that there are ways of configuring an Android device that improve the ICTM security invariant that Tor VPN can provide:
ACCESS_NETWORK_STATE permission, which gives access to all IP addresses on the device, along with a lot of other network interface information that can be used to track the user. For a good overview of all the information that is available by default, install Network Analyzer or use the Device ID test in our VPN Test App. Unfortunately, even privacy-preserving Android distributions such as GrapheneOS do not provide the ability to redact non-VPN network information and non-VPN IP addresses when a VPN is active. Additionally, on stock Android, apps can bypass the VPN interface by binding to the cell network interface, regardless of Always-on and Block Connections Android settings. Until those tickets are fixed:
When these properties are met, the app will not be linked to the device's Google account, which is a common source of deanonymization.
NOTE: Removing push notification permission is NOT ENOUGH to prevent apps from being able to register with Firebase (Google) to receive a push token that links the app to the Google account. See the Push Notification section of Known Weaknesses for more information. For now, if an app does not provide settings to disable notification registration, then you must use one of the following configurations instead. (For example: Session Messenger allows push registration to be disabled or switched to non-Google; Signal currently offers no such configuration).
It turns out that from the point of view of our ICTM security invariants, both of these are equivalent: they both result in Linkable Pseudonymity for both pseudonym-friendly apps and privacy-hostile apps because they significantly reduce the amount of linkable information, but they do not eliminate it. The primary reason is due to the remaining push notification linkability. See the Push Notification Linkability section of Known Weakness for more info. If the push notification linkability weakness is mitigated, then pseudonym-friendly apps will have Unlinkable Pseudonymity in this configuration when using push notifications. The first option accepts linkability through the Google account but mitigates deanonymization through careful management of this Google account. In this configuration, the user creates a new Google account over Tor and relies on the GrapheneOS Google Sandbox to provide pseudonymity for the device's Google account. In this sandbox, the system treats Google as a normal app, with revocable permissions and no access to hardware identifiers. Additionally, GrapheneOS requires the user to manually disable the Android Advertising ID. Doing so eliminates a large source of excess linkability. The Android Advertising ID is heavily used to link pseudonyms to location data. In the second option, the user configures a new privacy-enhanced Android device without a Google account but still uses push notifications with sandboxed Google Play Services on GrapheneOS. The user can use F-Droid or Aurora Store to install apps without a Google account. Without a Google account, there is less linkability risk between apps through other Google APIs other than push.
NOTE: The device must always use Tor to avoid linking its device push registration to a non-Tor IP address. This may be problematic in censorship scenarios where configuration information is delivered over push notifications. In this case, without a device Google account, it may be possible to clear registration data and re-register to remove linkability. But the effectiveness of this will depend on the data retention duration of the services involved for expired push tokens. See the Push Notification Linkability section of Known Weaknesses.
- These properties define this configuration:
- Configure with the IP Address Privacy Configuration to prevent Google Services and hostile apps from using the cell IP address for linkability.
- Optional Google Account Config:
- Create a new pseudonymous Google account over Tor for the device, using an SMS or VoIP phone number.
- The Android Advertising ID of this account has been disabled.
- Do not use the device phone number or Google account for app registration. Use a different online SMS or VoIP provider over Tor.
- If Tor VPN is in per-app mode, all Google Play Services and Google apps must be selected to use Tor in this configuration.
- Disable Private DNS and Connectivity Checks.
The active security invariant for a given scenario can be summarized in two matrices: one for Tor VPN per-app mode and one for Tor VPN all-app mode. These two matrices exactly represent the ICTM security invariant clauses from Section 2.3.
In this section, we list the known weaknesses of both stock Android and privacy-enhancing Android, where fixing a weakness would significantly improve the available security invariants.
For each weakness, we list the Consequences for the user and the mitigating configurations the user must perform, when possible.
We also provide fix Recommendations for developers of GrapheneOS, Android, and pseudonym-friendly apps.
The following Android privacy issues apply to all Android versions, including GrapheneOS and CalyxOS.
In all versions of Android, when apps have the ACCESS_NETWORK_STATE permission (which nearly all Android apps have), they can examine properties of all network interfaces, including the IP address. For a good overview of all the information that is available by default, install Network Analyzer or use our VPN Leak Test App.
Consequences: This weakness prevents Tor VPN from providing Network Privacy (or further invariants) to Privacy-hostile apps. This weakness also exposes the user to IP address leaks even for Pseudonym-friendly apps that disclose all device IP addresses during WebRTC calls. In both cases, the user must use their phone with a mobile WiFi hotspot, rather than a SIM card, to mitigate this weakness.
Recommendation: When a VPN is enabled, the Android OS should simulate non-VPN interfaces as disconnected, or it should spoof unused RFC1918 addresses for non-VPN interfaces. If addresses are spoofed, the system should not provide the same values to all apps, to prevent the use of spoofed values as identifiers (which likely already happens with IP address values today). These mitigations are essential because they enable VPNs to provide Network Privacy. Most VPN users naturally want their IP addresses to be unavailable to apps for tracking purposes.
All versions of Android (and also all versions of iOS) are currently subject to linkability through push notifications, even when the user has denied push notification permission to all apps.
When registering for Google's Firebase push notifications, apps obtain an FCM "token" from Firebase, which they submit to their servers. Their servers use this token to deliver messages to Google, who then uses the token ID to look up the device and send it the message.
Our VPN Leak Test App verifies that this registration ability is possible without any push notification permission, in the Device ID test.
This means that a series of record requests (sent first to the app developers and then to Google) will discover the Google account in use with a particular app. From there, even if there is no device Google account, the other push tokens associated with the device can be used to make further record requests to other app service providers for account data associated with their respective token IDs.
Because Google (and many apps) operate internationally, these requests can come from arbitrary jurisdictions. The Anti-Foreign Sanctions Law in China is one such example of a law that can be used for this purpose, although no direct reports of China using push notifications have been made public. It seems likely that Wyden's concerns did not come from nowhere, though.
This linkability is possible even for apps like Signal that do not send any actual content in the push notification and use it only as a wake-up notification. Because Signal still stores the token ID with the user's account on their servers, this linkability also exists for them.
This makes it impossible to have distinct pseudonyms for Signal, or any other app that registers with FCM, unless the user configures their device without Google Play Services or creates a separate user profile without Google Services for these apps.
Consequences: This weakness makes the Pseudonymous App Configuration impossible for many apps, because FCM push registration cannot actually be disabled by the user by denying push notification permission to an app. It also makes Pseudonymous Google Configuration have far more app linkability to the Google account (or device) than would otherwise be the case, linking many privacy-hostile apps to Google and to other pseudonym-friendly apps. The user has no real mitigation options, because disabling push notifications still allows this registration and resulting linkability.
Recommendations:
There are a few different approaches that can reduce the user's exposure to this linkability:
In our testing, we discovered that apps can bypass the VPN by using mDNS requests and SSDP activity. We have a reproduction case in our VPN Leak Test App. This test leaks on all versions of Android, including GrapheneOS. GrapheneOS has attempted to fix some multicast leaks, but our test app shows that these fixes are insufficient.
Additionally, these multicast leaks enable privacy-hostile apps to communicate on a local network, further linking user pseudonyms to other app activity on that same network.
This behavior is also observed in the wild, with Spotify engaging in communication over the local network through this bypass mechanism.
Consequences: This weakness allows Privacy-hostile apps to communicate on the local network to link their usage to other users on the network.
Recommendation: The Android OS should route this multicast behavior through the VPN interface. This will enable the VPN app to decide whether to allow these local network connections.
The Android ID is essentially a 64-bit identifier that is shared by all apps in a user profile with the same signing key.
This identifier persists across re-installations of the same app, which can be verified using our VPN Leak Test App using the Device Identifier test. Users who expect to be able to delete an app and then reinstall it to sign in under a different pseudonym will have their pseudonyms linked by Privacy-hostile apps that make use of this identifier.
Consequences: This weakness prevents users from being able to reinstall apps to change pseudonyms without linking those pseudonyms together. Basically, due to this weakness, once an app is linked to the user's real identity on a profile, that app will always be an Unmasked App, even after reinstallation. Users must install that app in a separate profile to avoid this linkability.
Recommendation: This ID should be randomized with every app installation, rather than persisting after uninstallation. This will allow users to delete an app to change pseudonyms.
For some reason, no Android permissions are necessary to determine the cell network ID and the provider name of the user's SIM card. This information can be used to determine the user's rough geographic location, depending on the range of the cell provider (typically at least country-level, but sometimes regional, state, or province-level). The Device ID test of our VPN Leak Test app displays this information. It is also visible in Network Analyzer.
Consequences: This weakness does not directly impact any of our privacy invariants, but it is generally bad for privacy.
Recommendation: These APIs should always return NULL/empty (the default when no eSIMs are configured), because this information is not necessary for app operation.
We observed that when WiFi calling is enabled for an activated eSIM, the device makes IPsec connections to the eSIM provider, bypassing the VPN.
Consequences: This weakness does not directly impact any of our privacy invariants, but it is generally bad for privacy in that it exposes the user's WiFi IP address to their cell network.
Recommendation: Allow VPN interfaces control of routing this connection, so that it may be disabled if the user chooses to block it.
Stock Android has a number of edge cases that can leak DNS or multicast, which can remove the Network Privacy invariant by revealing to the local network that a particular app may be in use.
Stock Android allows apps to bind to the cell network interface and then connect to an IP address, bypassing any VPN in place, regardless of Always-On or Block Connections VPN settings. Our VPN Test App has a reproduction case for this as part of the Leak Test. This leak is only possible over the cell network interface.
GrapheneOS fixed this issue in the 2025072700 Release.
Consequences: This leak allows Privacy-hostile apps to remove Network Privacy on stock Android. Users must use the IP Address Privacy Configuration and/or use GrapheneOS to prevent this leak.
Recommendations: Google shouldn't allow rogue apps to bind to the cell interface to bypass the VPN in Lockdown Mode, because VPN users expect that apps can't bypass the VPN in this mode.
On stock Android, user profile isolation can leak packets upon first use after restart.
Consequences: This leak prevents stock Android users from successfully using Isolated User Profile Configuration to isolate sensitive app activity. Users have to install GrapheneOS to mitigate this.
Recommendation: These leaks should be fixed, because users expect Always on VPN and Block Connection settings to work in all user profiles.
On stock Android, the device Google account has access to all hardware identifiers, as well as SIM card identifiers and phone number. This access typically means that any form of linking to the device Google account (through push notifications, Gmail use, or Google OAuth sign-in) typically means deanonymization of a pseudonym.
Consequences: It is difficult for a user to maintain a pseudonym even in Pseudonym-friendly apps without careful configuration.
Recommendations: Both privacy-conscious apps and Google should have more transparency with respect to actions that link the app's account to the device Google account, because users tend to expect that pseudonymity is not actively subverted behind their backs. In the meantime, the GrapheneOS Google Sandbox enables Pseudonymous Google Configuration.
Multiple issues with DNS exist in stock Android. Apps that use getaddrinfo() from the C library can bypass the VPN. Our VPN Leak Test app reproduces this leak as part of the main Leak Test.
Additional, DNS leaks can happen if the VPN malfunctions or shuts down.
Consequences: DNS leaks can erode Network Privacy by allowing local ISPs to determine which apps are in use. Users must use GrapheneOS to avoid these leaks.
Recommendations: GrapheneOS has fixed these issues. Google Android should upstream these fixes, because users expect that their DNS activity will not bypass their VPN.
Android has a secure setting Settings.Secure.always_on_vpn_lockdown_whitelist, which allows custom Android builds to define a list of apps that always bypass the VPN, regardless of VPN settings. Google and GrapheneOS both have this setting empty, but third-party Android builds may place their apps in this setting. The ReThink Firewall App has a ticket describing this issue.
Google Android also allows connectivity checks to bypass the VPN. GrapheneOS provides a setting to disable this.
Consequences: On Android rebuilds, various vendor apps may be exempted from the VPN, allowing them to connect outside of it. Users must use GrapheneOS to avoid these leaks.
Recommendations: Users should disable or remove vendor apps that they don't need.
The following weaknesses are unique to GrapheneOS. Note that the universal Android weaknesses also apply to GrapheneOS.
Additionally, the default-on behavior of the Android Advertising ID is another source of linkability between apps. GrapheneOS requires users to manually disable this ID, but this is not prominently documented during setup.
A better default would be to have the Android Advertising ID disabled by default or to provide a prominent setup step that educates users about this privacy risk.
We list this as a GrapheneOS-specific weakness because other privacy-preserving versions of Android randomize this ID automatically.
Consequences: Users who are not aware that they need to configure their Google account to disable this identifier will have all of their Privacy-hostile app activity linked to their Google account and to each other. Users must manually disable the Advertising ID in their Google account settings.
Recommendation: Similar to how GrapheneOS proxies the Location APIs, this API should be proxied to return a random or zeroed number, because this API is an extremely invasive source of linkability that enables aggregation of location and usage data across apps.
There are different ways you can contact the Tor Project and what information to include to help us resolve your issue quickly.
Tor relies on the support of users and volunteers around the world to help us improve our software and resources, so your feedback is extremely valuable to us (and to all Tor users).
When sending us feedback or reporting a bug, please include as many of these as possible:
There are several ways to reach us, so please use what works best for you.
We recommend asking for help on the Tor Forum. You will need to create an account to submit a new topic. Before you ask, please review our discussion guidelines. At the moment, for the fastest response, please write in English. If you found a bug, please use GitLab.
First, check if the bug is already known. You can search and read all the issues at https://gitlab.torproject.org/. To create a new issue, please request a new account to access Tor Project's GitLab instance and find the right repository to report your issue. Or you can report bugs or send us feedback anonymously through Anon Ticket without needing to create an account. We track all Tor Browser related issues at Tor Browser issue tracker. Issues related to our websites should be filed under the Web issue tracker.
If you need help installing or troubleshooting Tor Browser and the Tor Forum is blocked or censored where you are, you can reach out to us on Telegram https://t.me/TorProjectSupportBot. A Tor support specialist will assist you.
You can reach our support team with a text message to our WhatsApp number: +447421000612. This service is only available for text messages; videos or calls are not supported.
You can contact our team by sending a text message to our Signal number, +17787431312, or Signal username, @torsupport.89. Signal is a free and privacy-focused messaging app. This service is only available for text messages; videos or calls are not supported. After sending a message, our support agents will guide you and help troubleshoot your issue.
Send us an email to frontdesk@torproject.org.
In the subject line of your email, please tell us what you're reporting. The more specific your subject line is (e.g. "Connection failure", "feedback on website", "feedback on Tor Browser, "I need a bridge"), the easier it will be for us to understand and follow up. Sometimes when we receive emails without subject lines, they're marked as spam and we don't see them.
For the fastest response, please write in English, Spanish, and/or Portuguese if you can. If none of these languages works for you, please write in any language you feel comfortable with, but keep in mind it will take us a bit longer to answer as we will need help with translation to understand it.
You can always leave comments on the blog post related to the issue or feedback you want to report. If there is not a blog post related to your issue, please contact us another way.
You can find us in the #tor channel on OFTC or on #tor:matrix.org to give us feedback or report bugs/issues. We may not respond right away, but we do check the backlog and will get back to you when we can.
Learn how to connect to OFTC servers.
For reporting issues or feedback using email lists, we recommend that you do so on the one that is related to what you would like to report. A complete directory of our mailing lists can be found here.
For feedback or issues related to running a Tor relay: tor-relays
If you've found a security issue, please email security@torproject.org.
If you want to encrypt your mail, you can get the OpenPGP public key for this address from keys.openpgp.org. Here is the current fingerprint:
835B 4E04 F6F7 4211 04C4 751A 3EF9 EF99 6604 DE41
If you wish to participate in our bug bounty program, please be aware, submitting a security issue to a third-party website carries certain risks that we cannot control, as a result we'd prefer the report directly.
Find out how to contact the Tor Project for support, bug reports, and feedback.
When sending us a support request, feedback or reporting a bug, please include as much information possible:
Monday to Thursday: our user support channels on email, Telegram, WhatsApp, and Signal are operational.
Friday to Sunday: the helpline is closed. Please rest assured our team will get back to your messages on Monday.
There are several ways to reach us, so please use what works best for you.
We have several official Telegram bots and channels:
We recommend asking for help on the Tor Forum. You will need to create a account to submit a new topic. Please review our discussion guidelines and check the existing topics before asking. At the moment, for the fastest response, please write in English. If you found a bug, please use GitLab.
You can reach our support team with a text message to our WhatsApp number: +447421000612. This service is only available for text messages; videos or calls are not supported.
You can contact our team by sending a text message to our Signal number, +17787431312, or Signal username, @torsupport.89. Signal is a free and privacy-focused messaging app. Currently, our support channel is available in English, Russian, Farsi and focuses on helping Tor users in censored regions. The service is only available for text messages; videos, or calls are not supported. After sending a message, our support agents will guide you and help troubleshoot your issue.
Send us an email to frontdesk@torproject.org
In the subject line of your email, please tell us what you're reporting. The more specific your subject line is (e.g. "Connection failure", "feedback on website", "feedback on Tor Browser, "I need a bridge"), the easier it will be for us to understand and follow up. Sometimes when we receive emails without subject lines, they're marked as spam and we don't see them.
For the fastest response, please write in English, Russian, Farsi, Spanish, Hindi, Bangla and/or Portuguese if you can. If none of these languages works for you, please write in any language you feel comfortable with, but keep in mind it will take us a bit longer to answer as we will need help with translation to understand it.
You can find us in the #tor channel on OFTC or Tor User Support channel on Matrix. We may not respond right away, but we do check the backlog and will get back to you when we can.
Learn how to connect to IRC / Matrix.
First, check if the bug is already known. You can search and read all the issues at https://gitlab.torproject.org/. To create a new issue, please request a new account to access Tor Project's GitLab instance and find the right repository to report your issue. We track all Tor Browser related issues at Tor Browser issue tracker. Issues related to our websites should be filed under the Web issue tracker.