CVE-2026-8971 — MEDIUM (6.5)

Q: What is CVE-2026-8971?

CVE-2026-8971 is a vulnerability with a CVSS score of 6.5 (MEDIUM). Same-origin policy bypass in the Networking: JAR component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

Q: How severe is CVE-2026-8971?

CVE-2026-8971 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.

Q: Is there a patch for CVE-2026-8971?

Check the references section above for vendor advisories and patch information. Affected products include: Mozilla Firefox, Mozilla Thunderbird.

Vulnerability Description

Same-origin policy bypass in the Networking: JAR component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

CVSS Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

LOW

Integrity

LOW

Availability

NONE

Affected Products

Vendor	Product	Versions
Mozilla	Firefox	< 151.0.0
Mozilla	Thunderbird	< 151.0.0

Related Weaknesses (CWE)

CWE-346

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2032604Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-46/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-50/Vendor Advisory

FAQ

What is CVE-2026-8971?

CVE-2026-8971 is a vulnerability with a CVSS score of 6.5 (MEDIUM). Same-origin policy bypass in the Networking: JAR component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

How severe is CVE-2026-8971?

CVE-2026-8971 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-8971?

Check the references section above for vendor advisories and patch information. Affected products include: Mozilla Firefox, Mozilla Thunderbird.