8.8
High
CVE-2026-100776 Use-after-free in the JavaScript: WebAssembly component
Description
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 157 | earliest → < 157 | 157 |
| Firefox 153.4 | earliest → < 153.4 | 153.4 |
| Firefox 140.17 | earliest → < 140.17 | 140.17 |
| Thunderbird 157 | earliest → < 157 | 157 |
| Thunderbird 153.4 | earliest → < 153.4 | 153.4 |
| Thunderbird 140.17 | earliest → < 140.17 | 140.17 |
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