CVE-2025-1937

HIGH 7.5CVE-2025-1937 · Published 04/03/2025 · updated 05/10/2026

In short

CVE-2025-1937 is a HIGH (CVSS 7.5) vulnerability affecting firefox (mozilla), thunderbird (mozilla).
Chance of exploitation in the next 30 days (EPSS): 0.56%, higher than 46.8% of all vulnerabilities.
Fix: update to 115.21.0, 128.8.0, 135.0, 136.0 or later.

Package	Affected versions	Patched versions
firefox mozilla	`< 115.21.0< 128.8.0< 135.0`	`115.21.0128.8.0135.0`
thunderbird mozilla	`≥ 129.0, < 136.0< 128.8.0`	`136.0128.8.0`

Description

Memory safety bugs present in Firefox 135, Thunderbird 135, Firefox ESR 115.20, Firefox ESR 128.7, and Thunderbird 128.7. 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 136, Firefox ESR 115.21, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

References

bugzilla.mozilla.org/buglist.cgi · Exploit
mozilla.org/security/advisories/mfsa2025-14 · Vendor Advisory
mozilla.org/security/advisories/mfsa2025-15 · Vendor Advisory
mozilla.org/security/advisories/mfsa2025-16 · Vendor Advisory
mozilla.org/security/advisories/mfsa2025-17 · Vendor Advisory
mozilla.org/security/advisories/mfsa2025-18 · Vendor Advisory
openwall.com/lists/oss-security/2025/03/10/6 · Vendor Advisory
lists.debian.org/debian-lts-announce/2025/03/msg00006.html

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Package

Affected versions

Patched versions

firefox

mozilla

< 115.21.0< 128.8.0< 135.0

115.21.0128.8.0135.0

thunderbird

mozilla

≥ 129.0, < 136.0< 128.8.0

136.0128.8.0

Description

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