CVE-2026-117922
High
Description
Use-after-free in the Networking: WebSockets component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
SeverityHigh
CVSS8.8
Exploit probability—
Product
Firefox
PublishedOct 27, 2026
First seenOct 27, 2026
Weakness typeCWE-416Use after free
How to fix
Update
- Mozilla Firefox159 or later
- Mozilla Firefox ESR153.6 or later
- Mozilla Thunderbird153.6 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Mozilla Firefox | No range specified | 159 |
| Mozilla Firefox ESR | No range specified | 153.6 |
| Mozilla Thunderbird | No range specified | 153.6 |
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