CVE-2018-12403

critical

Published — · Modified —

CVSS v3

—

CVSS v2

—

VIR risk

9.5

Description

If a site is loaded over a HTTPS connection but loads a favicon resource over HTTP, the mixed content warning is not displayed to users. This vulnerability affects Firefox < 63.

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-2018-12403

vendor Authored 2026-05-27

Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2018-12403.html

vendor Authored 2026-05-27

Vendor advisory: arch — https://security.archlinux.org/ASA-201810-14

OS impact

OS	Version	Status	Fixed in
arch		fixed	`63.0-1`
sles		affected
debian	sid	fixed	`63.0-1`

References

https://security.archlinux.org/ASA-201810-14
https://www.suse.com/security/cve/CVE-2018-12403.html
https://security-tracker.debian.org/tracker/CVE-2018-12403

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