vulnerability
Red Hat: CVE-2025-4091: firefox: thunderbird: Memory safety bugs fixed in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10 (Multiple Advisories)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 8 | (AV:N/AC:H/Au:N/C:C/I:C/A:C) | Apr 29, 2025 | May 6, 2025 | Apr 15, 2026 |
Severity
8
CVSS
(AV:N/AC:H/Au:N/C:C/I:C/A:C)
Published
Apr 29, 2025
Added
May 6, 2025
Modified
Apr 15, 2026
Description
Memory safety bugs present in Firefox 137, Thunderbird 137, Firefox ESR 128.9, and Thunderbird 128.9. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 138, Firefox ESR 128.10, 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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