CVE-2025-8038
CRITICALCVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Lifecycle Timeline
1DescriptionNVD
Thunderbird ignored paths when checking the validity of navigations in a frame. This vulnerability was fixed in Firefox 141, Firefox ESR 140.1, Thunderbird 141, and Thunderbird 140.1.
AnalysisAI
Frame navigation validation bypass in Mozilla Firefox and Thunderbird allows unauthenticated remote attackers to violate security boundaries due to improper path checking (CWE-345). Affects Firefox <141, Firefox ESR <140.1, Thunderbird <141, and Thunderbird ESR <140.1. The CVSS 9.8 critical score reflects network-based exploitation with no user interaction required, enabling potential unauthorized access, data manipulation, and service disruption. No public exploit identified at time of analysis, though the network attack vector (AV:N) and low complexity (AC:L) suggest straightforward exploitation once technical details emerge.
Technical ContextAI
This vulnerability stems from CWE-345 (Insufficient Verification of Data Authenticity), specifically in Mozilla's frame navigation validation logic. Frames in web browsers enforce same-origin policy to prevent malicious sites from manipulating content across security boundaries. By ignoring path components during navigation validity checks, Firefox and Thunderbird failed to properly validate whether navigation requests should be permitted between frames with different paths under the same origin. This affects the browser's fundamental security model for isolating web content. The flaw impacts both the standard Firefox browser (cpe:2.3:a:mozilla:firefox) and extended support releases (ESR), as well as the Thunderbird email client which shares Mozilla's rendering engine. Path-based security checks are critical in web platform security, as they prevent attackers from bypassing origin restrictions through crafted navigation sequences.
RemediationAI
Vendor-released patches are available. Immediately upgrade Firefox standard release to version 141 or later, Firefox ESR to version 140.1 or later, Thunderbird standard release to version 141 or later, and Thunderbird ESR to version 140.1 or later. Mozilla auto-update mechanisms will deploy these fixes automatically for most users within 24-48 hours. Enterprise deployments using managed updates should prioritize rapid deployment given the critical CVSS score and network-based attack vector. Verify successful patching by navigating to About Firefox or About Thunderbird in the application menu. No effective workarounds exist short of disabling frame support entirely, which would break legitimate web functionality. Complete advisory details available at https://www.mozilla.org/security/advisories/mfsa2025-56/ (Firefox), https://www.mozilla.org/security/advisories/mfsa2025-59/ (Firefox ESR), https://www.mozilla.org/security/advisories/mfsa2025-61/ (Thunderbird), and https://www.mozilla.org/security/advisories/mfsa2025-63/ (Thunderbird ESR).
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