CVE-2017-17689

The S/MIME specification allows a Cipher Block Chaining (CBC) malleability-gadget attack that can indirectly lead to plaintext exfiltration, aka EFAIL.

This update for enigmail to version 2.0.4 fixes multiple issues.

Security issues fixed:

• CVE-2017-17688: CFB gadget attacks allowed to exfiltrate plaintext out of encrypted emails. enigmail now fails on GnuPG integrity check warnings for old Algorithms (bsc#1093151)
• CVE-2017-17689: CBC gadget attacks allows to exfiltrate plaintext out of encrypted emails (bsc#1093152)

This update also includes new and updated functionality:

• The Encryption and Signing buttons now work for both OpenPGP and S/MIME. Enigmail will chose between S/MIME or OpenPGP depending on whether the keys for all recipients are available for the respective standard
• Support for the Autocrypt standard, which is now enabled by default
• Support for Pretty Easy Privacy (p≡p)
• Support for Web Key Directory (WKD)
• The message subject can now be encrypted and replaced with a dummy subject, following the Memory Hole standard forprotected Email Headers
• keys on keyring are automatically refreshed from keyservers at irregular intervals
• Subsequent updates of Enigmail no longer require a restart of Thunderbird
• Keys are internally addressed using the fingerprint instead of the key ID

This update for enigmail to version 2.0.4 fixes multiple issues.

Security issues fixed:

• CVE-2017-17688: CFB gadget attacks allowed to exfiltrate plaintext out of encrypted emails. enigmail now fails on GnuPG integrity check warnings for old Algorithms (bsc#1093151)
• CVE-2017-17689: CBC gadget attacks allows to exfiltrate plaintext out of encrypted emails (bsc#1093152)

This update also includes new and updated functionality:

• The Encryption and Signing buttons now work for both OpenPGP and S/MIME. Enigmail will chose between S/MIME or OpenPGP depending on whether the keys for all recipients are available for the respective standard
• Support for the Autocrypt standard, which is now enabled by default
• Support for Pretty Easy Privacy (p≡p)
• Support for Web Key Directory (WKD)
• The message subject can now be encrypted and replaced with a dummy subject, following the Memory Hole standard forprotected Email Headers
• keys on keyring are automatically refreshed from keyservers at irregular intervals
• Subsequent updates of Enigmail no longer require a restart of Thunderbird
• Keys are internally addressed using the fingerprint instead of the key ID

These are all security issues fixed in the enigmail-2.2.4-1.4 package on the GA media of openSUSE Tumbleweed.

Damian Poddebniak, Christian Dresen, Jens Müller, Fabian Ising, Sebastian Schinzel, Simon Friedberger, Juraj Somorovsky, and Jörg Schwenk discovered that the KMail application of KDE PIM could be made to leak the plaintext of S/MIME encrypted emails when retrieving external content in emails. Under certain configurations, if a user were tricked into opening a specially crafted email, an attacker could possibly use this issue to obtain the plaintext of an encrypted email. This update mitigates the issue by preventing KMail from automatically loading external content. (CVE-2017-17689)

Jens Müller, Marcus Brinkmann, Damian Poddebniak, Sebastian Schinzel, and Jörg Schwenk discovered that the KMail application of KDE PIM could be made to leak the plaintext of S/MIME or PGP encrypted emails. If a user were tricked into replying to a specially crafted email, an attacker could possibly use this issue to obtain the plaintext of an encrypted email. (CVE-2019-10732)

It was discovered that the KMail application of KDE PIM could be made to attach files to an email without the user's knowledge. If a user were tricked into sending an email created by a specially crafted "mailto" link, an attacker could possibly use this issue to obtain sensitive files. This update mitigates the issue by displaying a warning to the user when files are attached in this way. (CVE-2020-11880)

It was discovered that the Account Wizard application of KDE PIM used HTTP rather than HTTPS when retrieving certain email server configurations. An attacker could possibly use this issue to cause email clients to use an attacker-controlled email server. This issue only affected Ubuntu 16.04 LTS. (CVE-2024-50624)

Damian Poddebniak, Christian Dresen, Jens Müller, Fabian Ising, Sebastian Schinzel, Simon Friedberger, Juraj Somorovsky, and Jörg Schwenk discovered that PIM Messagelib could be made to leak the plaintext of S/MIME encrypted emails when retrieving external content in emails. Under certain configurations, if a user were tricked into opening a specially crafted email using an application linked against PIM Messagelib, an attacker could possibly use this issue to obtain the plaintext of an encrypted email. This update mitigates the issue by preventing automatic loading of external content. (CVE-2017-17689)

Jens Müller, Marcus Brinkmann, Damian Poddebniak, Sebastian Schinzel, and Jörg Schwenk discovered that PIM Messagelib could be made to leak the plaintext of S/MIME or PGP encrypted emails. If a user were tricked into replying to a specially crafted email using an application linked against PIM Messagelib, an attacker could possibly use this issue to obtain the plaintext of an encrypted email. (CVE-2019-10732)

Damian Poddebniak, Christian Dresen, Jens Müller, Fabian Ising, Sebastian Schinzel, Simon Friedberger, Juraj Somorovsky, and Jörg Schwenk discovered that KMail could be made to leak the plaintext of S/MIME encrypted emails when retrieving external content in emails. Under certain configurations, if a user were tricked into opening a specially crafted email, an attacker could possibly use this issue to obtain the plaintext of an encrypted email. This update mitigates the issue by preventing KMail from automatically loading external content. This issue only affected Ubuntu 18.04 LTS. (CVE-2017-17689)

It was discovered that KMail could be made to attach files to an email without the user's knowledge. If a user were tricked into sending an email created by a specially crafted "mailto" link, an attacker could possibly use this issue to obtain sensitive files. (CVE-2020-11880)