CVE-2026-12330

EUVD-2026-37076
Incorrect boundary conditions in the Internationalization component. This vulnerability was fixed in Firefox ESR 140.12, Firefox ESR 115.37, and Thunderbird 140.12.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
mozillaCNA
5.4 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: 5.64%
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources (CNA/ADP records, vendor advisories, Enginsight analysis).
VendorProductVersionSource
mozillafirefox_esr
𝑥
< 115.37.0
CNA
mozillafirefox_esr
140.0 ≤
𝑥
< 140.12.0
CNA
mozillathunderbird_esr
140.0 ≤
𝑥
< 140.12.0
CNA
Debian logo
Debian Releases
Debian Product
Codename
firefox-esr
bookworm
140.12.0esr-1~deb12u1
fixed
bookworm (security)
153.5.1esr-1~deb12u1
fixed
forky
153.5.0esr-1
fixed
sid
153.5.1esr-1
fixed
trixie
140.15.0esr-1~deb13u1
fixed
trixie (security)
153.5.1esr-1~deb13u1
fixed
thunderbird
bookworm
1:140.12.0esr-1~deb12u1
fixed
bookworm (security)
1:140.17.0esr-1~deb12u1
fixed
forky
1:153.5.0esr-1
fixed
sid
1:153.5.1esr-1
fixed
trixie
1:140.12.0esr-1~deb13u1
fixed
trixie (security)
1:140.17.0esr-1~deb13u1
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
thunderbird
jammy
needs-triage
noble
needs-triage
questing
ignored
resolute
needs-triage
openSUSE logo
openSUSE / SLES Releases
openSUSE Product
Release
MozillaFirefox
suse enterprise desktop 15 SP7
140.12.0-150200.152.245.1
fixed
suse enterprise sap 12 SP5
140.12.0-112.321.1
fixed
suse enterprise sap 15 SP4
140.12.0-150200.152.245.1
fixed
suse enterprise sap 15 SP5
140.12.0-150200.152.245.1
fixed
suse enterprise sap 15 SP6
140.12.0-150200.152.245.1
fixed
suse enterprise sap 15 SP7
140.12.0-150200.152.245.1
fixed
suse enterprise server 12 SP3
140.12.0-112.321.1
fixed
suse enterprise server 12 SP5
140.12.0-112.321.1
fixed
suse enterprise server 15 SP4
140.12.0-150200.152.245.1
fixed
suse enterprise server 15 SP5
140.12.0-150200.152.245.1
fixed
suse enterprise server 15 SP6
140.12.0-150200.152.245.1
fixed
suse enterprise server 15 SP7
140.12.0-150200.152.245.1
fixed
MozillaFirefox-devel
suse enterprise desktop 15 SP7
140.12.0-150200.152.245.1
fixed
suse enterprise sap 12 SP5
140.12.0-112.321.1
fixed
suse enterprise sap 15 SP4
140.12.0-150200.152.245.1
fixed
suse enterprise sap 15 SP5
140.12.0-150200.152.245.1
fixed
suse enterprise sap 15 SP6
140.12.0-150200.152.245.1
fixed
suse enterprise sap 15 SP7
140.12.0-150200.152.245.1
fixed
suse enterprise server 12 SP3
140.12.0-112.321.1
fixed
suse enterprise server 12 SP5
140.12.0-112.321.1
fixed
suse enterprise server 15 SP4
140.12.0-150200.152.245.1
fixed
suse enterprise server 15 SP5
140.12.0-150200.152.245.1
fixed
suse enterprise server 15 SP6
140.12.0-150200.152.245.1
fixed
suse enterprise server 15 SP7
140.12.0-150200.152.245.1
fixed
MozillaFirefox-translations-common
suse enterprise desktop 15 SP7
140.12.0-150200.152.245.1
fixed
suse enterprise sap 12 SP5
140.12.0-112.321.1
fixed
suse enterprise sap 15 SP4
140.12.0-150200.152.245.1
fixed
suse enterprise sap 15 SP5
140.12.0-150200.152.245.1
fixed
suse enterprise sap 15 SP6
140.12.0-150200.152.245.1
fixed
suse enterprise sap 15 SP7
140.12.0-150200.152.245.1
fixed
suse enterprise server 12 SP3
140.12.0-112.321.1
fixed
suse enterprise server 12 SP5
140.12.0-112.321.1
fixed
suse enterprise server 15 SP4
140.12.0-150200.152.245.1
fixed
suse enterprise server 15 SP5
140.12.0-150200.152.245.1
fixed
suse enterprise server 15 SP6
140.12.0-150200.152.245.1
fixed
suse enterprise server 15 SP7
140.12.0-150200.152.245.1
fixed
MozillaFirefox-translations-other
suse enterprise desktop 15 SP7
140.12.0-150200.152.245.1
fixed
suse enterprise sap 15 SP4
140.12.0-150200.152.245.1
fixed
suse enterprise sap 15 SP5
140.12.0-150200.152.245.1
fixed
suse enterprise sap 15 SP6
140.12.0-150200.152.245.1
fixed
suse enterprise sap 15 SP7
140.12.0-150200.152.245.1
fixed
suse enterprise server 15 SP4
140.12.0-150200.152.245.1
fixed
suse enterprise server 15 SP5
140.12.0-150200.152.245.1
fixed
suse enterprise server 15 SP6
140.12.0-150200.152.245.1
fixed
suse enterprise server 15 SP7
140.12.0-150200.152.245.1
fixed
MozillaThunderbird
suse enterprise desktop 15 SP7
140.12.0-150200.8.277.1
fixed
suse enterprise sap 15 SP7
140.12.0-150200.8.277.1
fixed
suse enterprise server 15 SP7
140.12.0-150200.8.277.1
fixed
suse enterprise workstation 15 SP7
140.12.0-150200.8.277.1
fixed
MozillaThunderbird-translations-common
suse enterprise desktop 15 SP7
140.12.0-150200.8.277.1
fixed
suse enterprise sap 15 SP7
140.12.0-150200.8.277.1
fixed
suse enterprise server 15 SP7
140.12.0-150200.8.277.1
fixed
suse enterprise workstation 15 SP7
140.12.0-150200.8.277.1
fixed
MozillaThunderbird-translations-other
suse enterprise desktop 15 SP7
140.12.0-150200.8.277.1
fixed
suse enterprise sap 15 SP7
140.12.0-150200.8.277.1
fixed
suse enterprise server 15 SP7
140.12.0-150200.8.277.1
fixed
suse enterprise workstation 15 SP7
140.12.0-150200.8.277.1
fixed
Red Hat logo
Red Hat Enterprise Linux Releases
Red Hat Product
Release
firefox
RHEL 9
0:140.12.0-1.el9_8
fixed
firefox-x11
RHEL 9
0:140.12.0-1.el9_8
fixed
thunderbird
RHEL 9
0:140.12.0-1.el9_8
fixed
Amazon Linux logo
Amazon Linux Releases
Amazon Package
Release
firefox
Amazon Linux 2023
0:140.12.0-1.amzn2023.0.1
fixed
firefox-debuginfo
Amazon Linux 2023
0:140.12.0-1.amzn2023.0.1
fixed
firefox-debugsource
Amazon Linux 2023
0:140.12.0-1.amzn2023.0.1
fixed
thunderbird
Amazon Linux 2
0:140.12.0-1.amzn2.0.1
fixed
Common Weakness Enumeration
References
https://bugzilla.mozilla.org/show_bug.cgi?id=2029326
https://www.mozilla.org/security/advisories/mfsa2026-58/
https://www.mozilla.org/security/advisories/mfsa2026-59/
https://www.mozilla.org/security/advisories/mfsa2026-61/