Medium6.1Red Hat & Ubuntu Linux

Same-origin policy bypass in the Networking: Cookies component

CVE-2026-12304 Published Jun 16, 2026

CVE-2026-12304

Affected products & platforms

Red Hat & Ubuntu LinuxUnclassified

Summary

Same-origin policy bypass in the Networking: Cookies component. Red Hat rates this moderate (CVSS 6.1). Weakness: CWE-346. Affected package(s): firefox, thunderbird. Resolved in Red Hat advisory RHSA-2026:29940 — update the affected packages (`sudo dnf update`).

Affected versions

firefox-0:140.12.0-1.el9_8
firefox-0:140.12.0-1.el8_10
thunderbird-0:140.12.0-1.el8_10
firefox-0:140.12.0-1.el10_2
thunderbird-0:140.12.0-1.el10_2
thunderbird-0:140.12.0-1.el9_8

Official advisory · high-confidence parse· fetched 5 hours ago·verify at source

Fixed versions

RHSA-2026:29940

Official advisory · high-confidence parse· fetched 5 hours ago·verify at source

Mitigation checklist

Recommended fix / mitigation

Update the affected package(s) to the fixed version shipped in RHSA-2026:29940 (`sudo dnf update` / `yum update`).

Official advisory · high-confidence parse· fetched 5 hours ago·verify at source

Discussion(0)

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