CVE-2026-109782
High
Description
Mitigation bypass in the File Handling component. This vulnerability was fixed in Firefox ESR 153.5 and Thunderbird 153.5.
SeverityHigh
CVSS8.3
Exploit probability—
ProductFirefox ESR
PublishedOct 13, 2026
First seenOct 13, 2026
Weakness typeCWE-693CWE-693
How to fix
Update
- Firefox ESR153.5 or later
- Thunderbird153.5 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox ESR | No range specified | 153.5 |
| Thunderbird | No range specified | 153.5 |
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