CVE-2021-38500

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

Description

Mozilla developers reported memory safety bugs present in Firefox 92 and Firefox ESR 91.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Thunderbird < 78.15, Thunderbird < 91.2, Firefox ESR < 91.2, Firefox ESR < 78.15, and Firefox < 93.

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-2021:3755

vendor Authored 2026-05-27

Vendor advisory: rocky — https://errata.rockylinux.org/RLSA-2021:3838

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2021-38500

OS impact

OSVersionStatusFixed in
arch archfixed91.2.0-1
debian debiansidfixed93.0-1
debian debianbookwormfixed91.2.0esr-1
debian debianbullseyefixed78.15.0esr-1~deb11u1
debian debianforkyfixed91.2.0esr-1
debian debiantrixiefixed91.2.0esr-1
rockylinux rocky8fixed

References

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