Process isolation bypass using "javascript:" URI links in cross-origin frames
Vulnerability Description
A process isolation vulnerability in Thunderbird stemmed from improper handling of javascript: URIs, which could allow content to execute in the top-level document's process instead of the intended frame, potentially enabling a sandbox escape. This vulnerability was fixed in Firefox 138, Firefox ESR 128.10, Firefox ESR 115.23, Thunderbird 138, and Thunderbird 128.10.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:
- Nika Layzell
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1958350
- https://www.mozilla.org/security/advisories/mfsa2025-28/
- https://www.mozilla.org/security/advisories/mfsa2025-29/
- https://www.mozilla.org/security/advisories/mfsa2025-30/
- https://www.mozilla.org/security/advisories/mfsa2025-31/
- https://www.mozilla.org/security/advisories/mfsa2025-32/
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Timeline
CVSS Vectors
Weaknesses (CWE)
No CWE data available
MITRE ATT&CK TTPs
No associated TTPs found for this vulnerability.