CVE-2021-29974

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

Description

When network partitioning was enabled, e.g. as a result of Enhanced Tracking Protection settings, a TLS error page would allow the user to override an error on a domain which had specified HTTP Strict Transport Security (which implies that the error should not be override-able.) This issue did not affect the network connections, and they were correctly upgraded to HTTPS automatically. This vulnerability affects Firefox < 90.

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-2021-29974

vendor Authored 2026-05-27

Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2021-29974.html

vendor Authored 2026-05-27

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

OS impact

OSVersionStatusFixed in
arch archfixed90.0-1
suse slesaffected
debian debiansidfixed90.0-1

References

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