Tuta (email)

Tuta
Screenshot of Tutanota
Type of site
Webmail
Available inMultilingual
Headquarters
OwnerTutao GmbH
Employees14 (Nov. 2020)[1]
URLtuta.com
CommercialYes
RegistrationRequired
UsersOver 2 million
Launched2011
Current statusOnline
Tutanota client app
Developer(s)Tutao GmbH
Stable release
220.240321.0[2] / 21 March 2024; 8 months ago (21 March 2024)
Repositorygithub.com/tutao/tutanota/
Written inTypeScript and JavaScript
Operating systemMicrosoft Windows, macOS, Linux, iOS, Android
Platformx86-64, iOS, Android
LicenseGNU GPL v3
Websitetuta.com

Tuta, formerly Tutanota,[3] is an end-to-end encrypted email app and a freemium secure email service.[4] The service is advertisement-free; it relies on donations and premium subscriptions.[5] As of June 2023, Tutanota's owners claimed to have over 10 million users of the product.[6] The company announced a transition to 100% renewable electricity in March 2019.[7] This decision coincided with employee participation in Fridays for Future protests. On 1st October 2024, Tuta launched its standalone encrypted calendar app.[8] Tuta Mail has recently integrated post-quantum cryptography features through its new protocol - TutaCrypt replacing standard encryption methods like RSA-2048 and AES-256 for its newly created accounts after March 2024.[9][10]

History

[edit]
Tutanota logo from 2014 to 2024

Tutanota is derived from Latin and contains the words "tuta" and "nota" which means "secure message".[11] Tutao GmbH was founded in 2011 in Hanover, Germany.[12][13]

The goal of the developers for Tuta is to fight for email privacy. Their vision gained even more importance, when Edward Snowden revealed NSA's mass surveillance programs like XKeyscore in July 2013.[14][unreliable source?]

Since 2014, the software has been open-sourced and can be reviewed by outsiders on GitHub.[15][16]

In August 2018, Tuta became the first email service provider to release their app on F-Droid, removing all dependence on proprietary code. This was part of a full remake of the app, which removed dependence on GCM for notifications by replacing it with SSE. The new app also enabled search, 2FA and got a new reworked user interface.[17][18][non-primary source needed]

In November 2020, the Cologne court ordered monitoring of a single Tuta account that had been used for an extortion attempt. The monitoring function should only apply to future unencrypted emails this account receives and it will not affect emails previously received.[19][20]

On 7 November 2023, Tutanota announced it was rebranded to simply 'Tuta'.[21] The former domain name tutanota.com now redirects to the shorter tuta.com.[3]

On 11 November 2023, it was alleged that Tuta was being used as a honeypot for criminals with a backdoor from authorities. An ex-RCMP officer, Cameron Ortis, testified that the service was used as a storefront to lure criminals in and gain information on those who fell for it. He stated authorities were monitoring the whole service, feeding it to Five Eyes, which would disperse it back to the RCMP in order to gain more knowledge about the criminal underground. However, no evidence was ever presented to back up this statement, and Tuta refuted the claim.[22][23][24]

Services

[edit]

Tuta Mail

[edit]

"Tuta Mail" is Tuta’s initial and primary service. Tuta Mail is a fully end-to-end encrypted email service available for download on Android (Google, F-Droid, apk) and iOS. Tuta Mail has email clients for Linux, Windows and macOS. It can also be accessed through web browser. In 2024 Tuta introduced quantum-resistant algorithms in a hybrid protocol similar to Signal to protect the data against future attacks from quantum computers.

Tuta Calendar

[edit]

The "Tuta Calendar" is encrypted with post-quantum cryptography. The Tuta Calendar was first released as an integrated calendar in Tuta Mail. In October 2024, Tuta released it as a stand-alone calendar app available for iOS and Android.

Encryption

[edit]

When a user registers on Tuta, a private and public key is generated locally on their device. The private key is encrypted with the user's password before being sent to Tuta’s servers. User passwords are hashed using Argon2 and SHA256.[25][26]

Emails between Tuta users are automatically encrypted end-to-end.[27] For emails sent to external recipients, a password must be exchanged for symmetric encryption. Tuta also encrypts subject lines and attachments of emails and calendars with metadata and search indexes.[28] The email addresses of users, as well as those of senders and recipients, are stored in plain text. The timestamps indicating when an email was sent or received are also not encrypted.[29]

Tuta uses a standardized, hybrid method consisting of a symmetrical and an asymmetrical algorithm - AES with a length of 256 bit and RSA with 2048 bit.[30][31][32][33] To external recipients who do not use Tuta a notification is sent with a link to a temporary Tuta account. After entering a previously exchanged password, the recipient can read the message and reply end-to-end encrypted.[34][35]

Tuta Mail uses post-quantum cryptography features through its new protocol, TutaCrypt for its newly created accounts after March 2024. TutaCrypt combines traditional encryption methods with quantum-resistant algorithms to secure communications. It replaces the previous RSA-2048 keys with two new key pairs:

   Elliptic Curve Key Pair: Utilizes the X25519 curve for the Elliptic Curve Diffie-Hellman (ECDH) key exchange. 
   Kyber-1024 Key Pair: Implements post-quantum key encapsulation using the CRYSTALS-Kyber algorithm. 

TutaCrypt employs AES-256 in CBC mode alongside HMAC-SHA-256 for authenticated symmetric encryption. And the transition to TutaCrypt for old existing user accounts created before March 2024, will occur in near future.[36][37][38][39] Tuta also stated that it does not use PGP due to its limitations in encrypting subject lines and lack of flexibility for algorithm updates. S/MIME is also avoided due to critical vulnerabilities identified in 2018.[40]

Reception

[edit]

Reviews of Tech websites were generally positive for Tuta. In July 2023, TechRadar praised Tuta Mail as an "Excellent encrypted email platform" focusing on its broad features and intuitive design. However, it criticized the limitations in customer support and the cost of additional storage.[41] In June 2024, PCMag highlighted Tuta for its strong encryption and user-friendly interface with a rating of 4 out 5.[42] CyberNews rated 4.6 overall, but criticized Tuta for its lack of PGP and IMAP support. Also it pointed out Tuta's Headquarters - Germany as a drawback for being a part in Fourteen Eyes Alliance.[43]

Future

[edit]

Tuta is working on a cloud storage platform named "TutaDrive"[44] with a focus on post-quantum cryptography. The project, officially named "PQDrive - Development of a Post-Quantum Encrypted Online Storage," is funded by the German government's KMU-innovativ program (€1.5 million), which supports Small and medium-sized enterprises (SMEs) like Tuta. The project receives further support through a €600,000 collaboration with the University of Wuppertal, which will play a key role in research and development.[45]

Account deletion

[edit]

Tuta deletes free accounts that have not been logged into for 6 months. According to Tuta, this happens because of security reasons and for keeping the service free.[46]

Tuta has also been GDPR compliant since 2018.[better source needed][47][48]

Censorship

[edit]

Tuta has been blocked in Egypt since October 2019, and blocked in Russia since February 2020 for unknown reasons (although believed to be tied to actions against services operating outside of the country, especially those that involve encrypted communications).[49]

See also

[edit]

References

[edit]
  1. ^ "Huge community support enabled us to employ our 14th team member: Welcome Jonas!". Tutanota. 18 November 2020. Retrieved 28 December 2020.
  2. ^ "Release 220.240321.0 (Desktop)". 21 March 2024. Retrieved 29 March 2024.
  3. ^ a b Rudra, Sourav (2023-11-07). "Tutanota Rebranding as 'Tuta': What You Need to Know". It's FOSS. Retrieved 2023-11-07.
  4. ^ Natasha, Lomas (18 March 2015). "Tutanota, An Open Source Encrypted Gmail Alternative, Heads Out Of Beta". techcrunch.com. TechCrunch. Retrieved 4 November 2015.
  5. ^ "Tutanota prices". Tutanota. Retrieved 2022-09-25.
  6. ^ "Celebrate with us: Tutanota reaches 10 million users!". Tutanota. Retrieved 2024-05-14.
  7. ^ "Embracing Sustainability: Tuta's Commitment to a Greener Future". Tuta. Retrieved 2024-05-13.
  8. ^ "Exciting News from Tuta: Introducing the Tuta Calendar App!". [Tuta]. Retrieved 2024-09-05.
  9. ^ "Tuta Mail Adds New Quantum-Resistant Encryption to Protect Email". Bleeping Computer. Retrieved 2024-09-06.
  10. ^ "Post-Quantum Cryptography". Tuta. Retrieved 2024-09-06.
  11. ^ "What does the name "Tutanota" stand for?". Archived from the original on 2016-07-30. Retrieved 2016-08-06.
  12. ^ "5 of the Best Secure Email Services for Better Privacy". maketecheasier. 23 October 2015. Retrieved 13 March 2017.
  13. ^ "Amtsgericht Hannover Aktenzeichen: HRB 208014" (in German). German Company Register. 18 January 2012. Archived from the original on 22 September 2022. Retrieved 22 September 2022. Gesellschaftsvertrag vom 25.11.2011
  14. ^ "Encrypted Email: The Privacy Alternative to Gmail". StickyPassword. 20 October 2015. Archived from the original on 13 March 2017. Retrieved 13 March 2017.
  15. ^ "Secure Mail Service Tutanota Celebrates One Year Open Source". Tutanota. 2 September 2015. Retrieved 13 March 2017.
  16. ^ "Tutao GmbH". GitHub. Retrieved 2020-07-17.
  17. ^ Ivan (3 September 2018). "How Tutanota replaced Google's FCM with their own notification system". F-Droid. Retrieved 28 November 2018.
  18. ^ "Tutanota Becomes the Go-to Open Source Email Service with an App on F-Droid". Tutanota. 14 August 2018. Archived from the original on 13 August 2018. Retrieved 28 November 2018.
  19. ^ "German secure email provider Tutanota forced to monitor an account, after regional court ruling". msn.com. 8 December 2020. Retrieved 19 January 2021.
  20. ^ Moody, Glyn (9 Dec 2020). "German Court Orders Encrypted Email Service Tutanota To Backdoor One Account". techdirt. Retrieved 6 September 2021.
  21. ^ "Time to celebrate: Tutanota is now Tuta". tuta.com. 2023-11-07. Retrieved 2023-11-07.
  22. ^ "Tuta Is An Independent Company And Not Linked To Five Eyes Secret Services". Tutanota. Retrieved 2023-11-22.
  23. ^ Tunney, Catharine (12 Nov 2023). "Alleged RCMP leaker says he was tipped off that police targets had 'moles' in law enforcement". CBC. Archived from the original on 18 Nov 2023. Retrieved 22 Nov 2023.
  24. ^ "Encrypted Email Service Tuta Denies It's a 'Honeypot' for Five Eyes Intelligence". Gizmodo. 2023-11-15. Retrieved 2023-11-22.
  25. ^ "Best Encryption with KDF". Tuta. Retrieved 2024-09-06.
  26. ^ "What is a Password Hash". Tuta. Retrieved 2024-09-06.
  27. ^ "AES 256 Encryption". Tuta. Retrieved 2024-10-06.
  28. ^ "Tuta Encryption". Tuta. Retrieved 2024-09-06.
  29. ^ "Tuta Support General". Tuta. Retrieved 2024-09-06.
  30. ^ "What encryption algorithms does Tutanota use?". Archived from the original on 22 March 2015. Retrieved 17 August 2017.
  31. ^ "Security details about the encrypted email service Tutanota". Tutanota. Retrieved 2022-09-25. Tutanota uses symmetric (AES 128) and asymmetric encryption (AES 128 / RSA 2048) to encrypt emails end-to-end.
  32. ^ Bahar, Zen (2021-12-29). "Tutanota vs. ProtonMail: which one is better?". NordVPN. Retrieved 2022-09-22. Currently, Tutanota and Protonmail are [...] both offering end-to-end encryption.
  33. ^ "AES 256 Is Now Securing All Your Encrypted Tuta Emails". 2024-01-11.
  34. ^ "Tutanota FAQ". Tuta. Retrieved 2024-09-06.
  35. ^ "Tuta". Cyber Security Intelligence. Retrieved 2024-09-06.
  36. ^ "Tuta Mail Adds New Quantum-Resistant Encryption to Protect Email". Bleeping Computer. Retrieved 2024-09-06.
  37. ^ "Post-Quantum Cryptography". Tuta. Retrieved 2024-09-06.
  38. ^ "Tuta Mail Adds Quantum-Resistant Encryption via TutaCrypt". Restore Privacy. 11 March 2024. Retrieved 2024-09-06.
  39. ^ "TutaCrypt to Thwart Harvest Now, Decrypt Later Attacks". Security Boulevard. 14 March 2024. Retrieved 2024-09-06.
  40. ^ "Tuta Encryption". Tuta. Retrieved 2024-09-06.
  41. ^ "Tutanota secure email review". TechRadar. 21 July 2021. Retrieved 2024-09-06.
  42. ^ "Tuta Mail Review". PCMag. Retrieved 2024-09-06.
  43. ^ "Tutanota review: when privacy is a must". cybernews. 29 December 2021. Retrieved 2024-09-06.
  44. ^ "The Race Is On: Tutanota Launches Development of Post-Quantum Secure Cloud". Tuta. Retrieved 2024-05-13.
  45. ^ Rudra, Sourav (4 July 2023). "Tutanota Starts Working on Post-Quantum Secure Cloud". It's FOSS News. Retrieved 24 May 2024.
  46. ^ "Tutanota FAQ Inactive-accounts". Tutanota. Retrieved 2022-09-06.
  47. ^ "Press Inquiries & Media Kit". Tutanota. Retrieved 2022-09-24.
  48. ^ "GDPR-compliant email service: Tutanota offers easy email encryption for all businesses". Tutanota. Retrieved 2022-09-24.
  49. ^ Spadafora, Anthony 18 (18 February 2020). "Tutanota secure email service blocked in Russia". TechRadar. Retrieved 2020-02-22.{{cite web}}: CS1 maint: numeric names: authors list (link)
[edit]