9.8
Critical
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…
Description
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 Thunderbird 149.0.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 149.0.2, Firefox ESR 115.34.1, Firefox ESR 140.9.1, Thunderbird 149.0.2, and Thunderbird 140.9.1.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 149.0 | earliest → < 149.0.2 | 149.0.2 |
| Firefox 140.9 | earliest → < 140.9.1 | 140.9.1 |
| Firefox 115.34 | earliest → < 115.34.1 | 115.34.1 |
| Firefox ESR 140.9 | earliest → < 140.9.1 | 140.9.1 |
| Thunderbird 149.0 | earliest → < 149.0.2 | 149.0.2 |
| Thunderbird 140.9 | earliest → < 140.9.1 | 140.9.1 |
| Red Hat Enterprise Linux Server (v. 7 ELS) | Versions not published | |
| Red Hat Enterprise Linux AppStream EUS (v. 10.0) | Versions not published | |
| Red Hat Enterprise Linux AppStream (v. 10) | Versions not published |
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References
- Memory safety bugs fixed in Firefox ESR 115.34.1, Firefox ESR 140.9.1, Thunderbird ESR 140.9.1, Firefox 149.0.2 and Thunderbird 149.0.2 bugzilla.mozilla.org
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
Timeline
- Published
- Last modified
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