Mozilla Releases Firefox 157 with 76 Security Fixes, Shifts to Individual CVE Reporting
Mozilla Foundation has released the latest version of its web browser, Firefox 157, on September 29, 2026. The update resolves a total of 76 vulnerabilities tracked under individual CVEs and carries an overall severity rating of High.
The organization also updated its extended support releases. Firefox ESR 153.4 received fixes for 62 vulnerabilities including 34 rated High, while Firefox ESR 140.17 and Firefox ESR 115.42 were patched for 43 and 31 issues respectively.
Starting with this release, Mozilla changed its advisory publication policy. Previously, multiple internal memory safety problems were consolidated under one CVE; the new process assigns separate CVEs to each distinct issue.
The 76 vulnerabilities in Firefox 157 break down as 38 High, 29 Moderate, and 9 Low. High-severity problems include sandbox bypasses, privilege escalation, use-after-free conditions, uninitialized memory access, and JIT compilation errors. Affected components span DOM, Graphics, WebGPU, WebAssembly, and Networking.
The complete list of addressed CVEs includes: CVE-2026-100756 through CVE-2026-100792 (High), CVE-2026-96869 and CVE-2026-100794 through CVE-2026-100821 (Moderate), and CVE-2026-100822 through CVE-2026-100831 (Low).
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