CVE-2026-74967
Medium
Description
Same-origin policy bypass in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
SeverityMedium
CVSS5.4
Exploit probability—
Product
Mozilla Firefox
PublishedAug 18, 2026
First seenAug 18, 2026
Weakness typeCWE-346CWE-346
How to fix
Update
- mozilla firefox140.14.0, 153.1.0 or later
- mozilla thunderbird140.14.0, 153.1.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 140.14.0, 141.0 ≤ v < 153.1.0 | 140.14.0, 153.1.0 |
| mozilla thunderbird | v < 140.14.0, 141.0 ≤ v < 153.1.0 | 140.14.0, 153.1.0 |
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