VULNERABILITY INTELLIGENCE
CVE-2021-29974
CVSS score4.3 MEDIUM
EPSS probability0.84%
CISA KEVNot currently listed
Published2021-08-05
Last modified2026-06-17
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.