CVE-2026-92239
High
Description
A maliciously constructed IMAP line could cause an out-of-bounds buffer read. This vulnerability was fixed in Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.
SeverityHigh
CVSS8.1
Exploit probability—
Product
Mozilla Thunderbird
PublishedSep 15, 2026
First seenSep 15, 2026
Weakness typeCWE-125Out-of-bounds read
How to fix
Update
- mozilla thunderbird140.16.0, 153.3.0, 156.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla thunderbird | v < 140.16.0, 141.0 ≤ v < 153.3.0, 154.0 ≤ v < 156.0 | 140.16.0, 153.3.0, 156.0 |
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