CVE-2024-7531

Published: 6 August 2024

Calling `PK11_Encrypt()` in NSS using CKM_CHACHA20 and the same buffer for input and output can result in plaintext on an Intel Sandy Bridge processor. In Firefox this only affects the QUIC header protection feature when the connection is using the ChaCha20-Poly1305 cipher suite. The most likely outcome is connection failure, but if the connection persists despite the high packet loss it could be possible for a network observer to identify packets as coming from the same source despite a network path change. This vulnerability affects Firefox < 129, Firefox ESR < 115.14, and Firefox ESR < 128.1.

Notes

mozjs* contain a copy of the SpiderMonkey JavaScript engine. It
is not feasible to backport security fixes to the mozjs*
packages, as such, marking them as ignored.
starting with Ubuntu 22.04, the firefox package is just a script
that installs the Firefox snap
starting with Ubuntu 24.04, the thunderbird package is just a
script that installs the Thunderbird snap

Status

Severity score breakdown

References

• https://www.cve.org/CVERecord?id=CVE-2024-7531
• https://www.mozilla.org/en-US/security/advisories/mfsa2024-33/#CVE-2024-7531
• https://www.mozilla.org/en-US/security/advisories/mfsa2024-34/#CVE-2024-7531
• https://bugzilla.mozilla.org/show_bug.cgi?id=1905691
• https://www.mozilla.org/security/advisories/mfsa2024-33/
• https://www.mozilla.org/security/advisories/mfsa2024-34/
• https://www.mozilla.org/security/advisories/mfsa2024-35/
• https://ubuntu.com/security/notices/USN-6966-1
• NVD
• Launchpad
• Debian