CVE-2020-15680

critical

Published — · Modified —

CVSS v3

—

CVSS v2

—

VIR risk

9.5

Description

If a valid external protocol handler was referenced in an image tag, the resulting broken image size could be distinguished from a broken image size of a non-existent protocol handler. This allowed an attacker to successfully probe whether an external protocol handler was registered. This vulnerability affects Firefox < 82.

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-2020-15680

vendor Authored 2026-05-27

Vendor advisory: arch — https://security.archlinux.org/ASA-202011-1

OS impact

OS	Version	Status	Fixed in
arch		fixed	`82.0-1`
debian	sid	fixed	`82.0-1`

References

https://security.archlinux.org/ASA-202011-1
https://security-tracker.debian.org/tracker/CVE-2020-15680

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