CVE-2026-8091
Critical
Description
Incorrect boundary conditions in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 150, Thunderbird 150, Firefox ESR 140.10.1, Thunderbird 140.10.1, and Firefox ESR 115.35.2.
SeverityCritical
CVSS9.8
Exploit probability—
Product
Mozilla Firefox
PublishedMay 7, 2026
First seenMay 7, 2026
Weakness typeCWE-754CWE-754CWE-805CWE-805
How to fix
Update
- mozilla firefox115.35.2, 140.10.1 or later
- mozilla thunderbird140.10.1 or later
Vendor advisories
- access.redhat.com/errata/RHSA-2026:22708
- access.redhat.com/errata/RHSA-2026:22408
- access.redhat.com/errata/RHSA-2026:24719
- access.redhat.com/errata/RHSA-2026:19157
- access.redhat.com/errata/RHSA-2026:19153
- access.redhat.com/errata/RHSA-2026:19588
- access.redhat.com/errata/RHSA-2026:20586
- access.redhat.com/errata/RHSA-2026:22712
- access.redhat.com/errata/RHSA-2026:24718
- access.redhat.com/errata/RHSA-2026:24345
- access.redhat.com/errata/RHSA-2026:25014
- access.redhat.com/errata/RHSA-2026:22847
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 115.35.2, 140.0 ≤ v < 140.10.1 | 115.35.2, 140.10.1 |
| mozilla thunderbird | 140.0 ≤ v < 140.10.1 | 140.10.1 |
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