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VULNERABILITIES

CVE-2026-8950 Details

Description

Same-origin policy bypass in the Networking: HTTP component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Metrics

CVSS 3.x Severity and Vector Strings:

CNA: CISA-ADPCVSS-B:9.3 CRITICALVector:CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

References to Advisories, Solutions, and Tools

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URLSource(s)Tag(s)
https://bugzilla.mozilla.org/show_bug.cgi?id=1965430 [email protected]Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-46/ [email protected]Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-48/ [email protected]Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-50/ [email protected]Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-51/ [email protected]Vendor Advisory

Weakness Enumeration

CWE-IDCWE NameSource
CWE-346Origin Validation ErrorCISA-ADP

Affected Products

ProductVersions
mozilla firefox
< 140.11.0
< 151.0.0

CPE

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

Remediation

  • No remediation found in references.
mozilla thunderbird
< 140.11
< 151.0.0

CPE

  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*

Remediation

  • No remediation found in references.

Change History

6 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2026-8950
NVD Published Date:
May 19, 2026
NVD Last Modified:
Jun 17, 2026
Source:
[email protected]
CVE-2026-8950 Details - Not Deferred