CVE-2026-6784

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 and Thunderbird 150.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1536243%2C1745382%2C1851073%2C1893400%2C1963301%2C2001319%2C2002899%2C2012436%2C2014435%2C2016901%2C2019916%2C2020486%2C2020612%2C2020817%2C2021788%2C2022051%2C2022367%2C2022431%2C2023302%2C2023670%2C2024225%2C2024238%2C2024240%2C2024265%2C2024367%2C2024369%2C2024424%2C2024760%2C2025281%2C2025361%2C2025387%2C2025466%2C2025954%2C2025958%2C2026278%2C2026292%2C2026297%2C2026378%2C2027148%2C2027287%2C2027341%2C2027384%2C2027427%2C2027694%2C2027993%2C2028009%2C2028270%2C2028416%2C2028524%2C2029295%2C2029699%2C2029800%2C2029801
https://www.mozilla.org/security/advisories/mfsa2026-30/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-33/	Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-6784
https://bugzilla.redhat.com/show_bug.cgi?id=2460084
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-6784.json

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mozilla:firefox:::::-:::*
	cpe:2.3:a:mozilla:thunderbird:::::-:::*

History

26 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) Errores de seguridad de memoria presentes en Firefox 149 y Thunderbird 149. Algunos de estos errores mostraron evidencia de corrupción de memoria y presumimos que con suficiente esfuerzo algunos de estos podrían haber sido explotados para ejecutar código arbitrario. Esta vulnerabilidad fue corregida en Firefox 150 y Thunderbird 150.

Information

Published : 2026-04-21 13:16

Updated : 2026-10-26 21:10

NVD link : CVE-2026-6784

Mitre link : CVE-2026-6784

CVE.ORG link : CVE-2026-6784

JSON object : View

Products Affected

mozilla

firefox
thunderbird

CWE

CWE-125

Out-of-bounds Read

CWE-416

Use After Free

CWE-787

Out-of-bounds Write

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