OneCRL

Mozilla Releases Firefox 158.0.1 Security Update Fixing High-Severity Vulnerabilities and Compromised Certificates

Mozilla Foundation has published Firefox 158.0.1 on October 20, 2026, delivering fixes for four CVEs rated at high overall severity. Two vulnerabilities received a High rating, including a boundary condition flaw in the SVG component tracked as CVE-2026-113399 and a certificate blocklist issue identified as CVE-2026-113470. The update also refreshes the OneCRL list to block an intermediate certificate from eMudhra that was compromised earlier in the month. Mozilla delivered the updated blocklist via RemoteSettings on October 17 and embedded the changes directly into the browser release. This approach ensures compromised certificates remain blocked even when RemoteSettings is disabled or network access is unavailable. One Moderate and one Low severity issue complete the set of addressed flaws.