CVE-2026-16381

Same-origin policy bypass in the Networking: DNS component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2041001	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/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-72/	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-07-21 13:17

Updated : 2026-07-24 15:19

NVD link : CVE-2026-16381

Mitre link : CVE-2026-16381

CVE.ORG link : CVE-2026-16381

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-346

Origin Validation Error

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