CVE-2026-4697
Modified Modified - Updated After Analysis

Boundary Error in Firefox Web Codecs Risks Memory Corruption

Publication date: 2026-03-24

Last updated on: 2026-06-30

Assigner: Mozilla Corporation

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.

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Meta Information

Published
2026-03-24
Last Modified
2026-06-30
Generated
2026-07-06
AI Q&A
2026-03-24
EPSS Evaluated
2026-07-04
NVD
CVE-2026-4697
EUVD
EUVD-2026-14812

Affected Vendors & Products

Showing 2 associated CPEs
Vendor Product Version / Range
mozilla firefox to 149.0 (exc)
mozilla firefox to 140.9.0 (exc)

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Exploitability

CWE
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KEV
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CWE ID Description
CWE-754 The product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product.
CWE-787 The product writes data past the end, or before the beginning, of the intended buffer.

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Executive Summary

This vulnerability is caused by incorrect boundary conditions in the Audio/Video: Web Codecs component of Firefox. It affects versions of Firefox earlier than 149 and Firefox ESR earlier than 140.9.

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