9.8
Critical
CVE-2026-84142 Internally found bugs present in Thunderbird 154
Description
Internally found bugs present in Thunderbird 154. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155 and Thunderbird 155.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 155 | earliest → < 155 | 155 |
| Thunderbird 155 | earliest → < 155 | 155 |
References
- Moderate Severity internally found bugs fixed in Thunderbird 155 bugzilla.mozilla.org
- Low Severity internally found bugs fixed in Thunderbird 155 bugzilla.mozilla.org
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
Timeline
- Published
- Last modified
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