5.4
Medium
CVE-2026-84120 Use-after-free in the Audio/Video component
Description
Use-after-free in the Audio/Video component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 155 | earliest → < 155 | 155 |
| Firefox 153.2 | earliest → < 153.2 | 153.2 |
| Firefox 140.15 | earliest → < 140.15 | 140.15 |
| Firefox 115.40 | earliest → < 115.40 | 115.40 |
| Thunderbird 155 | earliest → < 155 | 155 |
| Thunderbird 153.2 | earliest → < 153.2 | 153.2 |
| Thunderbird 140.15 | earliest → < 140.15 | 140.15 |