Firefox Developer Edition (en-US) 151.0
Firefox Developer Edition (en-US) 151.0, released May 13, 2026, fixes 88 CVEs in Firefox Developer Edition (en-US). None of them is reported as exploited. Patch Radar priority: Urgent. The latest Firefox Developer Edition (en-US) is 156.0, which also fixes every one of these CVEs.
Superseded. The latest Firefox Developer Edition (en-US) is 156.0, which also fixes every CVE on this page. Install that instead.
Priority of the 88 CVEs
Applies to
| Product | Version |
|---|---|
| Firefox Developer Edition (en-US) | 151.0 |
CVEs this fix closes
| Priority | CVE | Title | CVSS | EPSS | Exploitation |
|---|---|---|---|---|---|
| Urgent | CVE-2026-8948 | Same-origin policy bypass in the DOM: Networking component | 9.1 | 0.0042 | None reported |
| Urgent | CVE-2026-6768 | Mitigation bypass in the Networking: Cookies component | 9.8 | 0.0029 | None reported |
| Urgent | CVE-2026-6760 | Mitigation bypass in the Networking: Cookies component | 9.8 | 0.0028 | None reported |
| Urgent | CVE-2026-5735 | Memory safety bugs fixed in Firefox 149.0.2 and Thunderbird 149.0.2 | 9.8 | 0.0027 | None reported |
| High | CVE-2026-6770 | Other issue in the Storage: IndexedDB component | 8.8 | 0.0388 | None reported |
| High | CVE-2026-6746 | Use-after-free in the DOM: Core & HTML component | 8.8 | 0.0095 | None reported |
| High | CVE-2026-6758 | Use-after-free in the JavaScript: WebAssembly component | 7.5 | 0.0081 | None reported |
| High | CVE-2026-8956 | Integer overflow in the Networking: JAR component | 9.8 | 0.0061 | None reported |
| High | CVE-2026-8949 | Integer overflow in the Widget: Win32 component | 7.5 | 0.0058 | None reported |
| High | CVE-2026-8946 | Incorrect boundary conditions in the Audio/Video: Web Codecs component | 7.5 | 0.0056 | None reported |
| High | CVE-2026-8953 | Sandbox escape due to use-after-free in the Disability Access APIs component | 9.6 | 0.0053 | None reported |
| High | CVE-2026-6785 | Memory safety bugs fixed in Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird ESR 140.10, Firefox 150 and Thunderbird 150 | 8.8 | 0.0051 | None reported |
| High | CVE-2026-6786 | Memory safety bugs fixed in Firefox ESR 140.10, Thunderbird ESR 140.10, Firefox 150 and Thunderbird 150 | 8.8 | 0.0050 | None reported |
| High | CVE-2026-8390 | Use-after-free in the JavaScript: WebAssembly component | 7.3 | 0.0050 | None reported |
| High | CVE-2026-6757 | Invalid pointer in the JavaScript: WebAssembly component | 8.8 | 0.0049 | None reported |
| High | CVE-2026-6750 | Privilege escalation in the Graphics: WebRender component | 8.8 | 0.0048 | None reported |
| High | CVE-2026-8975 | Memory safety bugs fixed in Thunderbird 140.11 and Thunderbird 151 | 8.8 | 0.0047 | None reported |
| High | CVE-2026-8954 | Incorrect boundary conditions, integer overflow in the Audio/Video component | 7.5 | 0.0043 | None reported |
| High | CVE-2026-8389 | JIT miscompilation in the JavaScript Engine: JIT component | 8.8 | 0.0042 | None reported |
| High | CVE-2026-8959 | Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component | 9.6 | 0.0042 | None reported |
| High | CVE-2026-8947 | Use-after-free in the DOM: Bindings (WebIDL) component | 7.5 | 0.0041 | None reported |
| High | CVE-2026-8968 | Denial-of-service due to invalid pointer in the Audio/Video: Web Codecs component | 7.5 | 0.0041 | None reported |
| High | CVE-2026-6749 | Information disclosure due to uninitialized memory in the Graphics: Canvas2D component | 8.8 | 0.0040 | None reported |
| High | CVE-2026-6747 | Use-after-free in the WebRTC component | 8.8 | 0.0040 | None reported |
| High | CVE-2026-6748 | Uninitialized memory in the Audio/Video: Web Codecs component | 9.8 | 0.0040 | 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.