Mozilla Firefox 153.5.0
Mozilla Firefox 153.5.0, released October 6, 2026, fixes 40 CVEs in Mozilla Firefox. None of them is reported as exploited. Patch Radar priority: Urgent. The latest Mozilla Firefox is 159.0.1, which also fixes every one of these CVEs.
Superseded. The latest Mozilla Firefox is 159.0.1, which also fixes every CVE on this page. Install that instead.
Priority of the 40 CVEs
Applies to
| Product | Version |
|---|---|
| Mozilla Firefox | 153.5.0 |
CVEs this fix closes
| Priority | CVE | Title | CVSS | EPSS | Exploitation |
|---|---|---|---|---|---|
| Urgent | CVE-2026-74943 | Use-after-free in the Graphics: ImageLib component | 9.8 | 0.0096 | None reported |
| Urgent | CVE-2026-74964 | Integer overflow in the Graphics component | 9.8 | 0.0060 | None reported |
| Urgent | CVE-2026-74986 | Site isolation issue in the CSS Parsing and Computation component | 9.1 | 0.0056 | None reported |
| Urgent | CVE-2026-74985 | Privilege escalation in the Enterprise Policies component | 9.8 | 0.0053 | None reported |
| Urgent | CVE-2026-74961 | Side-channel in the Web Audio component | 9.1 | 0.0044 | None reported |
| Urgent | CVE-2026-74936 | Use-after-free in the JavaScript: WebAssembly component | 9.8 | 0.0040 | None reported |
| Urgent | CVE-2026-74944 | Use-after-free in the DOM: Core & HTML component | 9.8 | 0.0040 | None reported |
| Urgent | CVE-2026-74959 | Mitigation bypass in the Storage: Cache API component | 9.1 | 0.0034 | None reported |
| High | CVE-2026-74945 | Information disclosure in the Graphics: Text component | 7.5 | 0.0071 | None reported |
| High | CVE-2026-74988 | Internally found bugs fixed in Thunderbird ESR 153.1 and Thunderbird 154 | 9.8 | 0.0061 | None reported |
| High | CVE-2026-74977 | Integer overflow in the Graphics component | 7.5 | 0.0060 | None reported |
| High | CVE-2026-74990 | Internally found bugs fixed in Thunderbird ESR 140.14, Thunderbird ESR 153.1 and Thunderbird 154 | 9.8 | 0.0053 | None reported |
| High | CVE-2026-74982 | Denial-of-service in the Widget component | 7.5 | 0.0053 | None reported |
| High | CVE-2026-74987 | Internally found bugs fixed in Thunderbird ESR 140.14, Thunderbird ESR 153.1 and Thunderbird 154 | 9.8 | 0.0052 | None reported |
| High | CVE-2026-74966 | Information disclosure in the Form Autofill component | 7.5 | 0.0044 | None reported |
| High | CVE-2026-74969 | Use-after-free in the Layout: Text and Fonts component | 8.8 | 0.0040 | None reported |
| High | CVE-2026-74978 | Clickjacking issue in the Widget component | 8.1 | 0.0038 | None reported |
| High | CVE-2026-74946 | Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component | 8.8 | 0.0033 | None reported |
| High | CVE-2026-74983 | Mitigation bypass in the Data Loss Prevention component | 8.1 | 0.0033 | None reported |
| High | CVE-2026-74971 | Information disclosure in the DOM: UI Events & Focus Handling component | 7.5 | 0.0032 | None reported |
| High | CVE-2026-74941 | Privilege escalation in the Graphics: CanvasWebGL component | 8.8 | 0.0032 | None reported |
| High | CVE-2026-74976 | JIT miscompilation in the JavaScript Engine: JIT component | 7.5 | 0.0032 | None reported |
| High | CVE-2026-74949 | Privilege escalation due to use-after-free in the Graphics: Canvas2D component | 8.8 | 0.0032 | None reported |
| High | CVE-2026-74948 | Information disclosure in the Graphics component | 7.5 | 0.0031 | None reported |
| High | CVE-2026-74935 | Privilege escalation in the DOM: Networking component | 8.8 | 0.0031 | None reported |
Patch Radar data is free to use with attribution. Terms and how to credit it.
Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.