Instant Messenger Chat

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Anonymous Chat, IRC, XMPP in Whonix.

General Safety Advice[edit]

Info Tip: Most existing instant messenger protocols are unsafe from a privacy point of view. This is not a Whonix-specific problem, but a general problem with instant messengers.

It is estimated that within 10 to 15 years, Quantum Computers will break today's common asymmetric public-key cryptography algorithms used for web encryption (https), e-mail encryption (GnuPG...), SSH and other purposes. See Post-Quantum Cryptography (PQCrypto).

It is recommended to review the Do not Mix Anonymity Modes section in conjunction with this entry. For a comprehensive comparison of instant messengers, see herearchive.org.

Encryption[edit]

Tor exit relays can eavesdrop on communications if encryption to the server is disabled. Depending on the protocol which an instant messenger is using, encryption might be disabled by default or not even supported. Tails has noted that without encryption, Tor exit relays can see the contact list, all messages, file transfers, and audio/video. [1] While encryption to the server prevents exit relay eavesdropping, it still leaves one problem unresolved: server logging.

High-risk users should also bear in mind that even in the event that strong and secure end-to-end encryption is used -- for example encrypted chat using .onion connections only (staying within the Tor network) -- advanced adversaries are capable of compromising the trusted computing base (TCB) [2] of nearly all platforms: [3]

All proper end-to-end encrypted (E2EE) messaging systems store private key(s) exclusively on user's device (endpoint). The holy grail of attacks against E2EE systems is called exfiltration where the sensitive data, namely the private keys or plaintext messages, are stolen from the endpoint. The attack is directed against the trusted computing base (TCB) of the target system. The overwhelming majority of TCBs are connected to the network and compromising them with polished malware that exploits a zero-day vulnerability, is trivial and undetectable.

Another consideration is that even when using end-to-end encrypted applications, additional strong security protocols such as forward secrecyarchive.org [4] may not be available for group communication channels, see: More is Less: On the End-to-End Security of Group Chats in Signal, WhatsApp, and Threemaarchive.org.

Web Interfaces[edit]

Avoid using web interfaces for any messengers because they break end-to-end encryption (E2E). If the website can show the messages, it follows that the server, if malicious or compromised, could also view the messages. Locally running applications should be preferred. Web apps running on a foreign server accessed through the user's browser are more exposed and therefore have a higher security risk.

Server Logging[edit]

Encrypted server connections do not prevent the server gathering interesting information about users, such as common contacts and the regularity of communications. An example list includes:

  • account names
  • buddy list (list of contacts)
  • the exact date and time of logins
  • message timestamps
  • communication patterns like common contacts (see footnote) [5]

The content of messages will only be protected by using end-to-end encryption, for example OMEMOarchive.org. The threat of server logging can be completely removed with decentralized (server-less) instant messengers like OnionShare.

Jabber / XMPP[edit]

Jabber/XMPParchive.org is a libre server-federation protocol designed with openness in mind: "... All of the existing XMPP servers, clients, and programming libraries support the key features of an IM system, such as one-to-one and multi-party messaging, presence subscriptions and notifications, and contact lists."

The system is decentralized because there is no central authoritative server; anyone can run a server. Some users are confused on this point because there are a number of large and popular public XMPP servers (like jabber.org), to which many have subscribed. [6] Each network user has a unique XMPP address called a JID (Jabber ID). The JID is similar to an email address insofar as it has a username and domain name like username@example.com [7]

Safely using the protocol requires proper use of encryption (such as OMEMO), because it is unwise to trust server connections are properly encrypted between each other. Jabber privacy is also limited, as various adversaries are capable of observing which accounts are communicating. Jabber and Tor combined only guarantee pseudonymous communications, as while the user's current location is hidden, the social graph can still expose their true identity. For tips on operational security when chatting anonymously, see this articlearchive.org by The Interceptarchive.org. Also see: Why prefer open protocols such as Jabber/XMPP over proprietary ones such as ICQ?archive.org

IRC[edit]

When using IRC (Internet Relay Chat) inside Whonix-Workstation, the Ident Protocolarchive.org is automatically blocked because Whonix-Workstation is firewalled. Therefore the associated daemon will not identify the username which is linked with a particular TCP connection, as is normally the case.

The Tor Project Internet Relay Chatarchive.org page contains a number of important recommendations and tips for safe IRC use:

  • Use onion services when available.
    • Check self-signed certificates have the correct SSL/TLS certificate.
  • Cycle Tor circuits to evade censorship bans.
  • Chain VPNs and Tor for registration.
  • Use OTR (or OMEMO if available) for end-to-end encryption.
  • Distrust users and servers in general.
  • Avoid personally identifiable information in chats.
  • Check the user fingerprint before using IRC.
  • Harden the IRC client.
  • And more.

Legal Data Access[edit]

In 2021, a Freedom of Information request uncovered a FBI training document that summarizes the level of access US law enforcement has to various secure messaging services. Most importantly, it revealed there is some limited access to encrypted messages in iMessage, Line and WhatsApp, but not to messages sent with Signal, Telegram, Viber, WeChat and Wickr; refer to the comparison table below.

Table: Legal Access: Secure Messaging Service Comparison [8]

Application Legal Process and Other Details
Apple iMessage
  • Message content limited.
  • Subpoena: can render basic subscriber information.
  • 18 USC §2703(d): can render 25 days of iMessage lookups and from a target number.
  • Pen Register: no capability.
  • Search Warrant: can render backups of a target device; if target uses iCloud backup, the encryption keys should also be provided with content return can also acquire iMessages from iCloud returns if target has enabled Messages in iCloud.
Line
  • Message content limited.
  • Suspect’s and/or victim’s registered information (profile image, display name, email address, phone number, LINE ID, date of registration, etc.).
  • Information on usage.
  • Maximum of seven days worth of specified users’ text chats (only when E2EE has not been elected and applied and only when receiving an effective warrant; however, video, picture, files, location, phone call audio and other such data will not be disclosed).
Signal
  • No message content.
  • Date and time a user registered.
  • Last date of a user’s connectivity to the service.
Telegram
  • No message content.
  • Court order: For confirmed terrorist investigations [9] or copyright infringement [10], Telegram may disclose phone numbers, IP addresses, and email addresses to relevant authorities.
Threema
  • No message content.
  • Hash of phone number and email address, if provided by user.
  • Push Token, if push service is used.
  • Public Key.
  • Date (no time) of Threema ID creation.
  • Date (no time) of last login.
Viber
  • No message content.
  • Provides account (i.e. phone number) registration data and IP address at time of creation.
  • Message history: time, date, source number, and destination number.
WeChat
  • No message content.
  • Accepts account preservation letters and subpoenas, but cannot provide records for accounts created in China.
  • For non-China accounts, they can provide basic information (name, phone number, email, IP address), which is retained for as long as the account is active.
WhatsApp
  • Message content limited.
  • Subpoena: can render basic subscriber records.
  • Court order: Subpoena return as well as information like blocked users.
  • Search warrant: Provides address book contacts and WhatsApp users who have the target in their address book contacts.
  • Pen register: Sent every 15 minutes, provides source and destination for each message.
  • If target is using an iPhone and iCloud backups enabled, iCloud returns may contain WhatsApp data, to include message content.
Wickr
  • No message content.
  • Date and time account created.
  • Type of device(s) application is installed on.
  • Date of last use.
  • Number of messages.
  • Number of external IDs (email addresses and phone numbers) connected to the account, bot not to plaintext external IDs themselves.
  • Avatar image.
  • Limited records of recent changes to account setting such as adding or suspending a device (does not include message content or routing and delivery information).
  • Wickr version number.

Instant Messenger Selection Criteria[edit]

A recommendation if any can be made depends on the threat model, priorities of the user. An obvious recommendation is impossible at time of writing because no instant messenger exists with all of the minimum desired security properties.

Signal is adamant about phone number validation (see Phone Number Validation vs User Privacy) , registration by phone which leads to very bad usability for most users that wish to remain anonymous and/or hide their social graph from the server.

OMEMO encryption has amazing security properties but it's opt-in in all known chat programs, which is a huge usability issue. Meaning users could easily forget to enable it or due to bugs getting disabled. Furthermore, there are no known instant messengers that are serverless (and thereby hiding the user's social graph) as well as at the same time support OMEMO encryption. Unfortunately, only jabber based, server based instant messengers support OMEMO.

The most secure instant messenger would be serverless, peer to peer (p2p) over Tor onions with OMEMO encryption enabled by default. But no such instant messenger combining all security properties exist. The user can either choose a server dependent (jabber) OMEMO encrypted chat or serverless Tor onion to onion instant messenger.

Instant Messenger Security Properties Comparison[edit]

Table: Instant Messenger Security Properties Comparison

TODO: unfinished

Security Property Dino IM Gajim OnionShare
Serverless / peer to peer / onion to onion No No Yes, client to onion (server)
No risks introduced for hosting an Onion Service [11] Yes Yes No
Encrypted by default No No Yes
No usability issues that might lead to catastrophic event [12] No No Yes
Verifiability Yes (OMEMO) Yes (OMEMO) ?
Deniability Yes (OMEMO) Yes (OMEMO) ?
Forward Secrecy Yes (OMEMO) Yes (OMEMO) Yes, Tor provides forward secrecy.
Written in memory safe language No (C) Yes (python) Yes (python)

TODO: other features in separate table

  • Multiple Devices Support
  • Offline Messages / Backlog
  • File Transfer

Recommendation[edit]

Applications discussed in this chapter are listed in order of best usability and compatibility with Whonix, based on the opinion and experience of Whonix developers.

It should be noted that no single application listed here has a superior feature set. Users must make a choice based on personal preferences and their self-assessed threat modelarchive.org:

  1. Dino IM It provides good UX, a modern and clean look and OMEMO support. On the downside, it requires a Jabber server which weakens anonymity.
  2. Gajim has more Jabber users, is written in memory-safe python, supports offline messages, and can provide OMEMO-grade encryption. On the downside, it requires a Jabber server which weakens anonymity.
  3. OnionShare provides a serverless (hosted using a Tor onion service), secure, ephemeral and anonymous chat feature. It is particularly useful because it does not require account creation, is encrypted end-to-end and reduces the risk of messages being stored locally.
  4. Nheko Reborn is another desktop IM client for the Matrix protocol and can be used for IRC channels. The developers do not recommend it as a daily driver due to possible implementation bugs.

Dino IM[edit]

Overview[edit]

Dino IMarchive.org is a modern XMPP ("Jabber") Chat Client written in GTK+/Vala for GNU/Linux and is available in Debian. OMEMO is supported, but needs to be toggled in the chat window. OpenPGP is also supported.

Installation[edit]

Install package(s) dino-im.

A. Update the package lists and upgrade the systemarchive.org.

sudo apt update && sudo apt full-upgrade

B. Install the dino-im package(s).

Using apt command line parameter --no-install-recommendsarchive.org is in most cases optional.

sudo apt install --no-install-recommends dino-im

C. Done.

The procedure of installing package(s) dino-im is complete.

Dino IM is planned for inclusion by default in Whonix 16. One outstanding issue at present is broken OMEMO compatibility with Gajim users. [13]

Key Backup[edit]

In addition to the fingerprint displayed in clients, OMEMO uses session/ephemeral keys: as soon as you chat with someone, these keys are created and they are replaced with new ones after every message exchange.

Without the latest session keys, incoming messages cannot be decrypted. This means when session keys are imported from an older backup, problems are likely if the keys were used in between.

Both types of keys are stored in ~/.local/share/dino/omemo.db (a SQLite database). Problems are avoided so long as keys are not backed up while Dino is running and Dino is not started from the same database twice.

Gajim[edit]

Overview[edit]

Ubuntu provides a succinct overview of Gajim: [14]

Gajim is a free software, instant messaging client for the Jabber (XMPP) protocol which uses the GTK+ toolkit. It runs on GNU/Linux, BSD and Windows. The name Gajim is a recursive acronym for Gajim (is) a jabber instant messenger. The goal of Gajim is to provide a full featured and easy to use Jabber client. Gajim works nicely with GNOME, but does not require it to run. It is released under the GNU General Public License.

Gajim has various features, including: [15]

  • chat client synchronization
  • group chats
  • sending of pictures, videos and other files to friends or groups
  • secure end-to-end encryption via OMEMO or PGP
  • the option to keep and manage all chat history
  • connection compatibility with other messengers via transports, such as IRC
  • various other features are available via plugins

In 2021, audio/video is reportedly not functional in Gajim. Further, OTR support was dropped in Gajim release 1.0, but the OMEMO pluginarchive.org is an encryption alternative. [16]

Figure: Gajim Client in Whonix

Installation[edit]

Info Tip: Gajim dependencies and Debian instructions are always available herearchive.org.

The steps below install Gajim, along with the OMEMO encryption plugin and HTTP Upload pluginarchive.org (which is required for file transfers). [17] The latter plugin is fully integrated into the core Gajim software as of version 1.0. Upon first launch of the program, users can use an existing XMPP account or create a new one.

Update the package lists.

sudo apt update

Install gajim and gajim-httpupload. [18]

sudo apt install gajim gajim-httpupload

Start Gajim from the start menu or type in konsole.

gajim

[19]

Configuration[edit]

Account[edit]

On first launch, an Account Creation Wizard Dialog will appear. Use the wizard to either create a new account to connect to the jabber network or use an existing account. For new accounts, there are multiple jabber servers available and only a username and password is required to join. [20]

Gajim Settings[edit]

The following changes are recommended for better security and privacy.

Logs:

  • EditAccountsuncheck Save conversation logs for all contacts

Activity settings:

  • PreferencesStatusuncheck Away after [21]
  • PreferencesStatusuncheck Not available after

Privacy settings:

  • PreferencesAdvancedPrivacyuncheck
    • Allow client / OS information to be sent
    • Allow local system time information to be sent
    • Log encrypted chat session
    • Allow my idle time to be sent

Prevent auto-start:

  • PreferencesAdvancedapplicationsCustomclear fields for: [22]
    • Browser
    • Mail Client
    • File Browser

Network settings: [23] [24]

  • PreferencesAdvancedglobal proxyTor
  • PreferencesAdvancedglobal proxymangeTorcheck Use proxy authenticationleave username blank → leave password blank

Gajim cannot be installed by default in Whonix yet, as there is more development work TODO; see Dev/Gajim.

IRC Client[edit]

Undocumented

OnionShare[edit]

See OnionShare.

Quaternion[edit]

Overview[edit]

Quaternion is a Qt-based desktop IM client for the Matrix protocol. Matrix is an open, federated communications protocol. [25]

At time of writing, Quaternion did not support end-to-end encryptionarchive.org yet.

For example, it is possible to create an account on the tchncs.dearchive.org home server for a more private experience; less data is collected about users compared to the matrix.org home server. The privacy issues are inherent in the synapse server side software itself; refer to this listarchive.org for a full write-up. Besides federating with other Matrix instances, Quaternion supports bridging to IRC, Telegram and many other protocols. [26]

Installation[edit]

Install package(s) quaternion.

A. Update the package lists and upgrade the systemarchive.org.

sudo apt update && sudo apt full-upgrade

B. Install the quaternion package(s).

Using apt command line parameter --no-install-recommendsarchive.org is in most cases optional.

sudo apt install --no-install-recommends quaternion

C. Done.

The procedure of installing package(s) quaternion is complete.

Nheko Reborn[edit]

Overview[edit]

Nheko Reborn is: [27]

... a Qt-based chat client for Matrix, an open, federated communications protocol. The motivation behind the project is to provide a native desktop app for Matrix that feels more like a mainstream chat app and less like an IRC client.

The developers explicitly warn that although the current implementation of end-to-end encryption is functional, it may have bugs that affect security. Further, it may be necessary to bootstrap cross-signing keys in a different client. Online key backup is not supported, but this can be performed offline. Most major chat features are available such as: VoIP calls (voice and video); user registration; creating, joining and leaving rooms; sending and receiving invites/files/emojis and so on.

Refer to the Nheko Reborn GitHub READMEarchive.org for further information.

Installation[edit]

Install package(s) nheko.

A. Update the package lists and upgrade the systemarchive.org.

sudo apt update && sudo apt full-upgrade

B. Install the nheko package(s).

Using apt command line parameter --no-install-recommendsarchive.org is in most cases optional.

sudo apt install --no-install-recommends nheko

C. Done.

The procedure of installing package(s) nheko is complete.

Cwtch[edit]

Cwtch Introduction[edit]

Cwtcharchive.org (by Open Privacyarchive.org). [28]

related:

Testers only! Testers only!

Cwtch Whonix-Gateway Installation Steps[edit]

This application requires incoming connections through a Tor onion service. Supported Whonix-Gateway modifications are therefore necessary for full functionality; see instructions below.

For better security, consider using Multiple Whonix-Gateway and Multiple Whonix-Workstation. In any case, Whonix is the safest choice for running it. [29]

Extend the onion-grater whitelist in Whonix-Gateway (sys-whonix).

On Whonix-Gateway.

Add onion-grater profile.

sudo onion-grater-add 40_cwtch

[30]

Cwtch Whonix-Workstation Installation Steps[edit]

Unfortunately not installable from Debian package repositories at time of writing. [31]

Inside Whonix-Workstation.

1. Find latest version and download link.

By visiting upstream download page https://cwtch.im/download/#linuxarchive.org.

2. Download.

Note: Replace download link with newer version if available.

scurl-download https://cwtch.im/releases/cwtch-v1.14.0/cwtch-v1.14.0.tar.gz

3. Digital software signature verification.

  • Digital signatures: A tool enhancing download security. Commonly used across the internet.
  • Learn more: Curious? Learn more about digital software signatures.
  • Optional: Digital signatures are optional. If you've never used them before, there might be no need to start now.
  • No worries: New to digital software signatures? It's okay, no need to worry.
  • Not a requirement: Not mandatory for using Whonix, but an extra security measure for advanced users.

Unavailable. Apparently upstream does not provide digital signatures yet. Cwtch upstream feature request: digital software signatures - sign releasesarchive.org

4. Extract.

tar xvf cwtch*.tar.gz

5. Change directory.

cd ./cwtch

6. Run the Cwtch for Whonix installer.

./install-whonix.sh

6. Done.

Installation of cwtch has been completed.

Cwtch Usage[edit]

Inside Whonix-Workstation.

To start Cwtch.

/home/user/.local/bin/cwtch

Web Browser / JavaScript Clients[edit]

Web clients can provide weaker or stronger security depending on the user's threat model.

One disadvantage of web clients is that they rely on the server not attacking the user and stealing their encryption keys from the browser. Websites can target specific users with malicious JavaScript whereas with an installed application, the code is completely static. [32]

Furthermore, installed applications can utilize TLS certificate pinning to better mitigate man-in-the-middle attacks by eliminating the dependence on potentially compromised certificate authorities. Certificate pinning is already being extensively used by applications such as Signal [33], ProtonMail [34] and others.

In addition, the stateless design of Tor Browser will erase any keys created and approved by communicating parties. This can cause confusion about the trustworthiness of contacts in subsequent sessions -- one workaround is to use a dedicated install of Firefox for that purpose.

However, there are advantages to web clients too. Websites are much less privileged than installed applications and have no direct access to system resources. Common browsers also often employ browser sandboxing technologies to contain malicious websites even in the event of a browser exploit (unless chained with an additional sandbox escape exploit).

Element Web[edit]

Element Web Apparchive.org is a browser-based Matrix client. It can also be run from different platformsarchive.org.

Converse.js[edit]

Converse.jsarchive.org is an OMEMO browser client which is provided by some XMPP hosting services. However, chat encryption is only available on "Trusted Devices".

Deprecated Chat Clients[edit]

Introduction[edit]

The following is a list of chat clients which were previously documented on this page. It is not a list of all deprecated chat clients that have ever existed.

CoyIM[edit]

CoyIM is no longer included in Whonix due to technical issues. Namely, it is currently not available from Debian stable or backports package sources (packages.debian.org). [35] There is a chance it will be reintroduced when Whonix 16 (based on Debian bullseye) is released. Manual software installation might also be possible (see Install Software), but that procedure is undocumented by Whonix developers.

Nheko[edit]

The original Nheko application is no longer maintained and was last worked on in 2018. [36]

As an alternative, consider installing Nheko Reborn.

Pidgin[edit]

Pidgin supports most protocols and OTR end-to-end encrypted chat. However, it is not recommended because it has a very poor security recordarchive.org with many remotely exploitable bugs. Security researcher and developer Micah Lee notes this is the result of reliance on legacy protocols and the libpurple, libotr and libxml libraries which are: "... massive, written in C/C++, and are littered with memory corruption bugs. ..." [37]

RetroShare[edit]

Whonix developers no longer list RetroShare, which is a friend-to-friendarchive.org (peer-to-peer), decentralized network and not an anonymizing network. Encrypted RetroShare connections support chat, voice and video, mail, file-sharing, forums and Tor. [38] Although RetroShare is under active developmentarchive.org, [39] there are several serious concerns which disqualify a recommendation:

  • The RetroShare package is signed with weak 1024-bit keys (in late-2018).
  • A 2016 code review which focused on implementation vulnerabilities discovered multiple security issues: [40]
    • The attack surface is high due to the feature-rich codebase.
    • Systemic "insecure coding practice" was identified, particularly "...inconsistent return value checking and error handling, poor usage of explicit and implicit typecasting, and relaxed handling of adverse security edge-cases."
    • Within a 24-hour period, auditors had developed proof of concept exploits for web-like vulnerabilities, weak binary protections, and out of bound memory reads and remote memory corruption (promptly rectified by developers).
  • A coverity scan of the RetroShare code shows a large number of outstanding defects, along with a relatively high defect density. [41] [42]

Ricochet IM[edit]

Ricochet IM (original) is no longer recommended as a decentralized (server-less) option because it is not functional in Whonix and deprecated upstream by its original developers. Ricochet IM 'only' uses onion encryption and is difficult to set up and use. OTR or OMEMO-grade encryption is not available and offline messages are not supported. [43] [44] Ricochet Refresh is unsupported since it was broken in Whonix 15 despite all efforts to fix itarchive.org. A contributor submitted github pull requests [45] which were unfortunately rejected due to Ricochet Refresh's rewrite goslingarchive.org in development. The Ricochet Refresh was changed and Ricochet rewrite is now non-freedom softwarearchive.org. The chosen license for gosling (a rewrite of Ricochet Refresh) is the same non-freedom software licensearchive.org Commons Clausearchive.org.

non-freedom

See Avoid non-freedom software.

Related: Whonix Policy On Non-Freedom Software

An issue Ricochet-Refresh is now proprietaryarchive.org had been reported. According to the Ricochet-Refresh developer's replyarchive.org it seems unlikely that the license would be reverted to a Freedom Software license.

Update: Was reverted.

[46]

(archived documentation)

TorChat[edit]

TorChat has not been recommended by Whonix developers since late-2015. The reason is development has been at a standstillarchive.org since 2013 and the TorChat developer does not respond to other people, suggesting the project has been abandoned. TorChat is also an unofficial project and unaffiliated with The Tor Project. Since communication, support, active development and security fixes are essential for anonymity-related projects, modern software alternatives are recommended. [47]

Another reason to avoid TorChat is the findings of a 2015 security analysis [48] which inspected the protocol and Python implementation: [49]

It was found that although the design of TorChat is sound, its implementation has several flaws, which make TorChat users vulnerable to impersonation, communication confirmation and denial-of-service attacks.

Tor Messenger[edit]

Do not use Tor Messenger! It was deprecated by upstream developers in early-2018. [50]

Tox[edit]

Tox is a fully-featured, decentralized (server-less) option which employs strong encryption, but the software is in alpha status.

qTox has been removed from Whonixarchive.org due to serious security issues.

Other Software[edit]

For anonymous Voice over IP (VoIP) or encrypted, anonymous phone calls using the Tor anonymity network, see: VoIP.

If a messenger program is not listed in this chapter, it is for now recommended against. If readers feel any privacy-respecting chat clients are missing on this page, first search the Whonix forumsarchive.org to see if that application has been discussed in the recent past. Any additions to this page will be based on an objective analysis of the software's underlying strength and compatibility with Whonix. [51]

See Also[edit]

Footnotes / References[edit]

  1. See: https://tails.boum.org/todo/Pidgin_Protocol_Review/archive.org for an overview of Pidgin protocols and associated encryption features.
  2. "... the trusted computing base or TCB comprises the set of all hardware, software, and firmware components that are critical to establishing and maintaining its security. Typically, the TCB consists of an operating system with all its in-built security controls, individual system hardware, network hardware and software, defined security procedures and protocols, and the actual physical location of the system itself." Trusted Computing Base or "TCB"archive.org
  3. https://github.com/maqp/tfc/wiki/Security-design#the-issue-of-endpoint-securityarchive.org
  4. Advanced cryptographic ratchetingarchive.org:

    As we’ve discussed previously, “forward secrecy” is one of the critical security properties OTR is designed to provide. In contrast to the PGP protocol model, where messages to a recipient are encrypted with the same public key over and over again, OTR uses ephemeral key exchanges for each session. This is a critical feature of any modern secure protocol, because otherwise a network adversary who records (potentially years of) ciphertext traffic can later decrypt all of it if they manage to later compromise the one key that was used. By contrast, with ephemeral key exchanges, there is no key to compromise in the future (since the keys are only ephemerally in memory for a short time), so any recorded ciphertext should remain private.

  5. If the recipient knows the sender and has ever used a non-anonymous account or logged in without Tor, this information can be used to try and determine the sender's identity.
  6. Other popular public servers are listed herearchive.org.
  7. https://en.wikipedia.org/wiki/XMPParchive.org
  8. https://therecord.media/fbi-document-shows-what-data-can-be-obtained-from-encrypted-messaging-apps/archive.org
  9. https://telegram.org/privacy?setln=ru#8-3-law-enforcement-authoritiesarchive.org
  10. https://torrentfreak.com/telegram-discloses-personal-details-of-pirating-users-following-court-order-221130/archive.org
  11. There are more de-anonymization attacks against onion services than against Tor users who only use Tor as a client since it is possible to make onion services talk.
  12. Users assuming encryption was used while it actually has not been used.
  13. https://forums.whonix.org/t/dino-im-messenger/7773/22archive.org
  14. https://help.ubuntu.com/community/Gajimarchive.org
  15. https://gajim.org/archive.org
  16. https://dev.gajim.org/gajim/gajim/-/wikis/help/gajimfaq#does-gajim-support-audiovideoarchive.org
  17. Note this feature can be combined with OMEMO for encrypted file transfers.
  18. gajim-omemo is installed by default in Debian bullseye during the Gajim installation.
  19. anon-apps-configarchive.org which is installed by default will deactivate gajim plugin installer / updaterarchive.org because it is not secure.
  20. A new account can always be added with: EditAccountsNew
  21. To prevent needlessly leaking your activity to the server.
  22. For better security, this prevents the automatic start of these applications from the chat client.
  23. To set use of the Tor network, along with Stream Isolation.
  24. Whonix gajim instructions giving errorarchive.org. Proxy authentication is tested to work in Whonix 16 when the username and password are left blank in settings.
  25. https://packages.debian.org/bookworm/quaternionarchive.org
  26. https://matrix.org/bridges/archive.org
  27. https://packages.debian.org/bullseye/nhekoarchive.org
  28. Security considerations:
    • By using Whonix, additional protections are in place for greater security.
    • This application requires access to Tor's control protocol.
    • In the Whonix context, Tor's control protocol has dangerous features. The Tor control command GETINFO address reveals the real, external IP of the Tor client.
    • Whonix provides onion-grater, a Tor Control Port Filter Proxy - filtering dangerous Tor Control Port commands.
    • When this application is run inside Whonix-Gateway with an onion-grater whitelist extension, this will limit Whonix-Workstation application rights to Tor control protocol access only. Non-whitelisted Tor control commands such as GETINFO address are rejected by onion-grater in these circumstances. In the event Whonix-Workstation, it can't determine its own IP address via requesting to Tor Controller, as onion-grater filters the reply.
    • In comparison, if the application is run on a non-Tor focused operating system like Debian, it will have unlimited access to Tor's control protocol (a less secure configuration).
    • If the (non-)Whonix platform is used to host onion services, then running applications are more vulnerable to attacks against the Tor network compared to when Tor is solely used as a client; see also Onion Services Security.
    In conclusion, Whonix is the safest and correct choice for running this application.
  29. These instructions use the /usr/share/doc/onion-grater-merger/examples/40_cwtch.ymlarchive.org onion-grater profile packaged for Whonix. In the future it is conceivable that the upstream [https://git.openprivacy.ca/cwtch.im/cwtch-ui/src/branch/trunk/linux/cwtch-whonix.ymlarchive.org cwtch-whonix.yml onion-grater profile is more recent. In that case it might be necessary to replace /usr/share/doc/onion-grater-merger/examples/40_cwtch.yml with upstream's cwtch-whonix.yml until onion-grater in Whonix is upgraded to contain the new onion-grater profile.
  30. RFP: cwtch -- Privacy Preserving Infrastructure for Asynchronous, Decentralized, Multi-Party, and Metadata Resistant Applicationsarchive.org
  31. https://proton.me/blog/cryptographic-architecture-response/archive.org
  32. https://www.signal.org/blog/certifiably-fine/archive.org
  33. https://proton.me/blog/tls-ssl-certificate#Extra-security-precautions-taken-by-ProtonMailarchive.org
  34. https://forums.whonix.org/t/coyim-in-whonix-development-discussion/5901/16archive.org
  35. https://github.com/mujx/nhekoarchive.org

    This repository has been archived by the owner. It is now read-only.

  36. https://micahflee.com/2013/02/using-gajim-instead-of-pidgin-for-more-secure-otr-chat/archive.org
  37. Unlike other private P2P options, the F2F network can grow in size without compromising their users' identities. Also, passwords or digital signatures are required for authentication.
  38. See also: https://retroshareteam.wordpress.com/2021/03/15/release-notes-for-v0-6-6/archive.org
  39. https://www.elttam.com/blog/a-review-of-the-eff-secure-messaging-scorecard-pt1/archive.org
  40. https://scan.coverity.com/projects/retroshare-retrosharearchive.org
  41. For example, compare this result with the low number of defects and defect density of the Torarchive.org codebase.
  42. https://github.com/ricochet-im/ricochet/issues/72archive.org
  43. https://github.com/ricochet-im/ricochet/issues/405archive.org
  44. Ricochet IM was previously recommended in this section, since it passed a recent (2016) security audit with flying colors.
  45. Security Analysis of Instant Messenger TorChatarchive.org
  46. https://en.wikipedia.org/wiki/TorChat#Securityarchive.org
  47. Also see: https://forums.whonix.org/t/client-server-instant-messengers-im/3081archive.org

License[edit]

Whonix Chat wiki page Copyright (C) Amnesia <amnesia at boum dot org>
Whonix Chat wiki page Copyright (C) 2012 - 2023 ENCRYPTED SUPPORT LP <

This program comes with ABSOLUTELY NO WARRANTY; for details see the wiki source code.
This is free software, and you are welcome to redistribute it under certain conditions; see the wiki source code for details.

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