CVE-2021-29957

high
Published — · Modified —
CVSS v3
CVSS v2
VIR risk
8.0

Description

If a MIME encoded email contains an OpenPGP inline signed or encrypted message part, but also contains an additional unprotected part, Thunderbird did not indicate that only parts of the message are protected. This vulnerability affects Thunderbird < 78.10.2.

Predictions

Exploit likelihood
20%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2021-29957

vendor Authored 2026-05-27

Vendor advisory: rocky — https://errata.rockylinux.org/RLSA-2021:2264

vendor Authored 2026-05-27

Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2021-29957.html

vendor Authored 2026-05-27

Vendor advisory: arch — https://security.archlinux.org/ASA-202105-29

OS impact

OSVersionStatusFixed in
arch archfixed78.10.2-1
suse slesaffected
rockylinux rocky8fixed
debian debianbookwormfixed1:78.10.2-1
debian debianbullseyefixed1:78.10.2-1
debian debianforkyfixed1:78.10.2-1
debian debiansidfixed1:78.10.2-1
debian debiantrixiefixed1:78.10.2-1

References

Verify integrity in audit chain (admin only). AS-IS.