CVE-2026-16405

Information disclosure in the Networking: WebSockets component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2036591	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-68/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-70/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-71/
https://www.mozilla.org/security/advisories/mfsa2026-72/

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-07-21 13:17

Updated : 2026-07-22 20:16

NVD link : CVE-2026-16405

Mitre link : CVE-2026-16405

CVE.ORG link : CVE-2026-16405

JSON object : View

Products Affected

mozilla

firefox

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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