8.1
High
CVE-2025-5269 Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10
Description
Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox ESR 128.11 and Thunderbird 128.11.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox ESR 128.11 | earliest → < 128.11 | 128.11 |
| Thunderbird 128.11 | earliest → < 128.11 | 128.11 |
| Firefox 128.11 | earliest → < 128.11 | 128.11 |
References
- Memory safety bug fixed in Firefox ESR 128.11 and Thunderbird 128.11 bugzilla.mozilla.org
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
Timeline
- Published
- Last modified
Other CVEs of Firefox ESR
The 833 CVEs of Firefox ESR →
CVE-2026-5734
Memory safety bugs present in Firefox ESR 140.9.0, Thunderbird ESR 140.9.0, Firefox 149.0.1 and Thunderbird 149.0.1
8.1
High
CVE-2026-5732
Incorrect boundary conditions, integer overflow in the Graphics: Text component
8.8
High
CVE-2026-5731
Memory safety bugs present in Firefox ESR 115.34.0, Firefox ESR 140.9.0, Thunderbird ESR 140.9.0, Firefox 149.0.1 and…
9.8
Critical
CVE-2026-2447
Heap buffer overflow in libvpx
8.8
High