CVE-2026-92240: mozilla thunderbird

CVSS 9.1 (critical) · published 2026-09-15

A malicious or compromised IMAP server can trigger an out-of-bounds read in the IMAP response parser by sending an untagged '* ID' response, crashing Thunderbird. The affected parsing path is reachable before authentication. This vulnerability was fixed in Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

Affected products (NVD): mozilla thunderbird

Fixed in (NVD): 140.16.0, 153.3.0, 156.0

Weakness: CWE-125

Source: NVD CVE-2026-92240

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=2069113
• https://www.mozilla.org/security/advisories/mfsa2026-94/
• https://www.mozilla.org/security/advisories/mfsa2026-95/
• https://www.mozilla.org/security/advisories/mfsa2026-96/

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