CVE-2021-29984

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

Description

Instruction reordering resulted in a sequence of instructions that would cause an object to be incorrectly considered during garbage collection. This led to memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.13, Thunderbird < 91, Firefox ESR < 78.13, and Firefox < 91.

Predictions

Exploit likelihood
20%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: rocky — https://errata.rockylinux.org/RLSA-2021:3155

vendor Authored 2026-05-27

Vendor advisory: rocky — https://errata.rockylinux.org/RLSA-2021:3157

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2021-29984

vendor Authored 2026-05-27

Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2021-29984.html

vendor Authored 2026-05-27

Vendor advisory: arch — https://security.archlinux.org/ASA-202108-14

OS impact

OSVersionStatusFixed in
arch archfixed78.13.0-1
suse slesaffected
debian debiansidfixed91.0-1
debian debianbookwormfixed78.13.0esr-1
debian debianbullseyefixed78.13.0esr-1~deb11u1
debian debianforkyfixed78.13.0esr-1
debian debiantrixiefixed78.13.0esr-1
rockylinux rocky8fixed

References

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