CVE-2026-84138

Denial-of-service in the PDF Viewer component. This vulnerability was fixed in Firefox 155 and Thunderbird 155.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2056164	Issue Tracking
https://www.mozilla.org/security/advisories/mfsa2026-82/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-86/	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-09-01 13:20

Updated : 2026-09-03 18:17

NVD link : CVE-2026-84138

Mitre link : CVE-2026-84138

CVE.ORG link : CVE-2026-84138

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-400

Uncontrolled Resource Consumption

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