CVE-2025-5266

Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks. This vulnerability affects Firefox < 139, Firefox ESR < 128.11, Thunderbird < 139, and Thunderbird < 128.11.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTNIST
4.3 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
mozillaCNA
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CISA-ADPADP
4.3 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
CVEADP
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Base Score
CVSS 3.x
EPSS Score
Percentile: 17%
VendorProductVersion
mozillafirefox
𝑥
< 128.11.0
mozillafirefox
𝑥
< 139.0
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
firefox
sid
145.0.1-1
fixed
firefox-esr
bullseye
vulnerable
bullseye (security)
140.5.0esr-1~deb11u1
fixed
bookworm
128.14.0esr-1~deb12u1
fixed
bookworm (security)
140.5.0esr-1~deb12u1
fixed
trixie
140.4.0esr-1~deb13u1
fixed
trixie (security)
140.5.0esr-1~deb13u1
fixed
forky
140.5.0esr-1
fixed
sid
140.5.0esr-1
fixed
thunderbird
bullseye
vulnerable
bullseye (security)
1:140.5.0esr-1~deb11u1
fixed
bookworm
1:128.14.0esr-1~deb12u1
fixed
bookworm (security)
1:140.5.0esr-1~deb12u1
fixed
trixie
1:140.4.0esr-1~deb13u1
fixed
trixie (security)
1:140.5.0esr-1~deb13u1
fixed
forky
1:140.5.0esr-1
fixed
sid
1:140.5.0esr-1
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
mozjs78
questing
dne
plucky
dne
oracular
dne
noble
dne
jammy
ignored
focal
dne
firefox
questing
not-affected
plucky
not-affected
oracular
not-affected
noble
not-affected
jammy
not-affected
focal
dne
thunderbird
questing
not-affected
plucky
not-affected
oracular
not-affected
noble
not-affected
jammy
Fixed 1:128.12.0+build1-0ubuntu0.22.04.1
released
focal
dne
mozjs38
questing
dne
plucky
dne
oracular
dne
noble
dne
jammy
dne
focal
dne
bionic
needs-triage
mozjs52
questing
dne
plucky
dne
oracular
dne
noble
dne
jammy
dne
focal
ignored
bionic
ignored
mozjs68
questing
dne
plucky
dne
oracular
dne
noble
dne
jammy
dne
focal
ignored
mozjs91
questing
dne
plucky
dne
oracular
dne
noble
dne
jammy
ignored
focal
dne
mozjs102
questing
dne
plucky
dne
oracular
dne
noble
ignored
jammy
ignored
focal
dne
mozjs115
questing
dne
plucky
ignored
oracular
ignored
noble
ignored
jammy
dne
focal
dne
Common Weakness Enumeration
References
https://bugzilla.mozilla.org/show_bug.cgi?id=1965628
https://www.mozilla.org/security/advisories/mfsa2025-42/
https://www.mozilla.org/security/advisories/mfsa2025-44/
https://www.mozilla.org/security/advisories/mfsa2025-45/
https://www.mozilla.org/security/advisories/mfsa2025-46/
https://lists.debian.org/debian-lts-announce/2025/05/msg00043.html
https://lists.debian.org/debian-lts-announce/2025/05/msg00046.html