7.4
High
CVE-2026-4371 A malicious mail server could send malformed strings with negative lengths, causing the parser to read memory outside…
Description
A malicious mail server could send malformed strings with negative lengths, causing the parser to read memory outside the buffer. If a mail server or connection to a mail server were compromised, an attacker could cause the parser to malfunction, potentially crashing Thunderbird or leaking sensitive data. This vulnerability was fixed in Thunderbird 149 and Thunderbird 140.9.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Thunderbird 149 | earliest → < 149 | 149 |
| Thunderbird 140.9 | earliest → < 140.9 | 140.9 |
| Red Hat Enterprise Linux AppStream EUS (v. 10.0) | Versions not published | |
| Red Hat Enterprise Linux AppStream (v. 10) | Versions not published | |
| Red Hat Enterprise Linux AppStream (v. 8) | Versions not published | |
| Red Hat Enterprise Linux AppStream AUS (v. 8.2) | Versions not published | |
| Red Hat Enterprise Linux AppStream AUS (v.8.4) | Versions not published | |
| Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) | Versions not published | |
| Red Hat Enterprise Linux AppStream AUS (v.8.6) | Versions not published |
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References
- bugzilla.mozilla.org bugzilla.mozilla.org
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
Timeline
- Published
- Last modified
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