Mozilla Foundation has released the security update Firefox 158.0.1 on October 20, 2026, addressing multiple vulnerabilities and updating protections against a compromised intermediate certificate.
The release carries an overall importance rating of High and resolves four CVEs. Two issues are rated High, one Moderate, and one Low.
The High-severity flaws include a boundary condition vulnerability in the SVG component tracked as CVE-2026-113399 and a certificate blocklist problem identified as CVE-2026-113470.
For CVE-2026-113470, Mozilla responded to the compromise of an eMudhra intermediate certificate by updating the OneCRL blocklist on October 17. The updated list was distributed the same day through RemoteSettings.
The new browser version ensures that compromised certificates are blocked even if RemoteSettings is disabled or unavailable due to network restrictions.


