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CVE-2026-6748: Vulnerability in Mozilla Firefox

0
Critical
VulnerabilityCVE-2026-6748cvecve-2026-6748
Published: Tue Apr 21 2026 (04/21/2026, 12:40:45 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

Uninitialized memory in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 04/21/2026, 13:47:33 UTC

Technical Analysis

The vulnerability identified as CVE-2026-6748 involves uninitialized memory usage within the Audio/Video: Web Codecs component of Mozilla Firefox. Uninitialized memory vulnerabilities can lead to unpredictable behavior, including potential information disclosure or memory corruption. This vulnerability was fixed in Firefox 150 and Firefox ESR 140.10 as part of a broader set of memory safety fixes. The vendor advisories from Mozilla confirm the high impact of this issue and the availability of patches in the specified Firefox versions.

Potential Impact

The vulnerability has a high impact rating as per Mozilla's advisories. Uninitialized memory in the Web Codecs component could lead to memory safety issues, which may be exploitable to cause information disclosure or other memory corruption effects. However, there are no known exploits in the wild at the time of publication. The issue affects Firefox versions prior to 150 and ESR versions prior to 140.10.

Mitigation Recommendations

Mozilla has released official fixes for this vulnerability in Firefox 150 and Firefox ESR 140.10. Users and administrators should update to these versions or later to remediate the vulnerability. Since this is a client software vulnerability, applying the official update is the recommended and effective mitigation. No additional vendor-recommended mitigations or workarounds are indicated.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-04-21T12:40:45.603Z
Cvss Version
null
State
PUBLISHED
Remediation Level
null
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2026-30/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-32/","vendor":"Mozilla"}]

Threat ID: 69e7789819fe3cd2cdd1624c

Added to database: 4/21/2026, 1:16:08 PM

Last enriched: 4/21/2026, 1:47:33 PM

Last updated: 4/22/2026, 6:04:56 AM

Views: 5

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