CVE-2026-4697
High
Description
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
SeverityHigh
CVSS7.5
Exploit probability—
Product
Mozilla Firefox
PublishedMar 24, 2026
First seenMar 24, 2026
Weakness typeCWE-754CWE-754CWE-787Out-of-bounds write
How to fix
Update
- mozilla firefox140.9.0, 149.0 or later
Vendor advisories
- access.redhat.com/errata/RHSA-2026:8427
- access.redhat.com/errata/RHSA-2026:7843
- access.redhat.com/errata/RHSA-2026:8315
- access.redhat.com/errata/RHSA-2026:5931
- access.redhat.com/errata/RHSA-2026:6342
- access.redhat.com/errata/RHSA-2026:5932
- access.redhat.com/errata/RHSA-2026:6917
- access.redhat.com/errata/RHSA-2026:7840
- access.redhat.com/errata/RHSA-2026:8285
- access.redhat.com/errata/RHSA-2026:7858
- access.redhat.com/errata/RHSA-2026:8850
- access.redhat.com/errata/RHSA-2026:7842
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 140.9.0, v < 149.0 | 140.9.0, 149.0 |
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