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CVE-2026-6784: Vulnerability in Mozilla Firefox

0
High
VulnerabilityCVE-2026-6784cvecve-2026-6784
Published: Tue Apr 21 2026 (04/21/2026, 12:41:13 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

Memory safety bugs present in Firefox 149 and Thunderbird 149. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 150.

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 04/21/2026, 13:31:26 UTC

Technical Analysis

CVE-2026-6784 encompasses memory safety bugs found in Firefox 149 and Thunderbird 149, some of which showed evidence of memory corruption that could be exploited to run arbitrary code. Mozilla addressed these vulnerabilities in Firefox 150 and Thunderbird 150 releases. The advisory is part of a larger security update (MFSA 2026-30) that fixes multiple high-impact memory safety and other security issues across Firefox and Thunderbird. No CVSS score is provided, but the impact is assessed as high by Mozilla.

Potential Impact

The vulnerabilities could allow attackers to exploit memory corruption bugs to execute arbitrary code within the context of the affected applications. This poses a high security risk to users running Firefox 149 or Thunderbird 149. No known exploits in the wild have been reported at the time of publication.

Mitigation Recommendations

Mozilla has released official fixes for these vulnerabilities in Firefox 150 and Thunderbird 150. Users and administrators should upgrade to these versions or later to remediate the issue. Since this is not a cloud service, remediation depends on applying the vendor's update. Patch status is confirmed by the vendor advisory.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-04-21T12:41:12.823Z
Cvss Version
null
State
PUBLISHED
Remediation Level
null
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2026-30/","vendor":"Mozilla"}]

Threat ID: 69e778a219fe3cd2cdd1662e

Added to database: 4/21/2026, 1:16:18 PM

Last enriched: 4/21/2026, 1:31:26 PM

Last updated: 4/21/2026, 3:00:55 PM

Views: 3

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