CVE-2020-26951

critical
Published 2020-11-30 ยท Modified 2020-11-30
CVSS v3
โ€”
CVSS v4 NEW
โ€”
not yet in upstream
VIR risk
9.5

Description

A parsing and event loading mismatch in Firefox's SVG code could have allowed load events to fire, even after sanitization. An attacker already capable of exploiting an XSS vulnerability in privileged internal pages could have used this attack to bypass our built-in sanitizer. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.

Predictions

Exploit likelihood
20%
Patch ETA
โ€”

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ€” if you've already worked around this in production โ€” publish your fix to the community-verified tier.

โœš Propose a mitigation on Community โ†’ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

suse SUSE Affected 1 release
VersionStatusFixed in
โ€” Affected โ€”
arch Arch Fixed 1 release
VersionStatusFixed in
โ€” Fixed 83.0-1
debian Debian Fixed 5 releases
VersionStatusFixed in
trixie Fixed 78.5.0esr-1
sid Fixed 83.0-1
forky Fixed 78.5.0esr-1
bullseye Fixed 78.5.0esr-1
bookworm Fixed 78.5.0esr-1
redhat Red Hat Fixed 1 release
VersionStatusFixed in
8 Fixed โ€”

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

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