CVE-2025-5269

Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 128.11 and Thunderbird < 128.11.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTNIST
8.1 HIGH
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
mozillaCNA
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CISA-ADPADP
8.1 HIGH
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 24%
VendorProductVersion
mozillafirefox
𝑥
< 128.11.0
mozillathunderbird
𝑥
< 128.11.0
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
firefox-esr
bullseye
vulnerable
bullseye (security)
140.3.1esr-1~deb11u1
fixed
bookworm
128.14.0esr-1~deb12u1
fixed
bookworm (security)
140.3.1esr-1~deb12u1
fixed
trixie
128.14.0esr-1~deb13u1
fixed
trixie (security)
140.3.1esr-1~deb13u1
fixed
forky
140.3.1esr-2
fixed
sid
140.3.1esr-2
fixed
thunderbird
bullseye
vulnerable
bullseye (security)
1:140.3.0esr-1~deb11u1
fixed
bookworm
1:128.14.0esr-1~deb12u1
fixed
bookworm (security)
1:140.3.0esr-1~deb12u1
fixed
trixie
1:128.14.0esr-1~deb13u1
fixed
trixie (security)
1:140.3.0esr-1~deb13u1
fixed
forky
1:140.3.0esr-1
fixed
sid
1:140.3.1esr-1
fixed
Common Weakness Enumeration
References
https://bugzilla.mozilla.org/show_bug.cgi?id=1924108
https://www.mozilla.org/security/advisories/mfsa2025-44/
https://www.mozilla.org/security/advisories/mfsa2025-46/