CVE-2026-100775
Critical
Description
Sandbox escape in the Graphics component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
SeverityCritical
CVSS9.6
Exploit probability—
Product
Mozilla Firefox
PublishedSep 29, 2026
First seenSep 29, 2026
Weakness typeCWE-693CWE-693
How to fix
Update
- mozilla firefox115.42.0, 140.17.0, 153.4.0, 157.0.0 or later
- mozilla thunderbird140.17.0, 153.4.0, 157.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | 115.0.1 ≤ v < 115.42.0, 140.0.0 ≤ v < 140.17.0, 153.0.0 ≤ v < 153.4.0, 154.0.0 ≤ v < 157.0.0 | 115.42.0, 140.17.0, 153.4.0, 157.0.0 |
| mozilla thunderbird | 140.0 ≤ v < 140.17.0, 153.0 ≤ v < 153.4.0, 154.0 ≤ v < 157.0 | 140.17.0, 153.4.0, 157.0 |
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