CVE-2021-29970

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

Description

A malicious webpage could have triggered a use-after-free, memory corruption, and a potentially exploitable crash. *This bug could only be triggered when accessibility was enabled.*. This vulnerability affects Thunderbird < 78.12, Firefox ESR < 78.12, and Firefox < 90.

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-2021:2743

vendor Authored 2026-05-27

Vendor advisory: rocky — https://errata.rockylinux.org/RLSA-2021:2883

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2021-29970

vendor Authored 2026-05-27

Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2021-29970.html

vendor Authored 2026-05-27

Vendor advisory: arch — https://security.archlinux.org/ASA-202107-20

vendor Authored 2026-05-27

Vendor advisory: arch — https://security.archlinux.org/ASA-202107-21

OS impact

OSVersionStatusFixed in
arch archfixed78.12.0-1
suse slesaffected
debian debiansidfixed90.0-1
debian debianbookwormfixed78.12.0esr-1
debian debianbullseyefixed78.12.0esr-1
debian debianforkyfixed78.12.0esr-1
debian debiantrixiefixed78.12.0esr-1
rockylinux rocky8fixed

References

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