vulnerability
Red Hat: CVE-2025-4083: firefox: thunderbird: Process isolation bypass using "javascript:" URI links in cross-origin frames (Multiple Advisories)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 9 | (AV:N/AC:M/Au:N/C:C/I:C/A:P) | Apr 29, 2025 | May 6, 2025 | Jun 17, 2026 |
Severity
9
CVSS
(AV:N/AC:M/Au:N/C:C/I:C/A:P)
Published
Apr 29, 2025
Added
May 6, 2025
Modified
Jun 17, 2026
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.
Solutions
redhat-upgrade-firefoxredhat-upgrade-firefox-debuginforedhat-upgrade-firefox-debugsourceredhat-upgrade-firefox-x11redhat-upgrade-thunderbirdredhat-upgrade-thunderbird-debuginforedhat-upgrade-thunderbird-debugsource
References
Rapid7 Labs
2026 Global Threat Landscape Report
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