Skip to content
Fencer Vulns
medium 5.4

CVE-2026-12330 json

Incorrect boundary conditions in the Internationalization component

published 2026-06-16 4 mo ago modified 2026-10-26 14 d ago also EUVD-2026-37076

cvss
5.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits
0
none known

Summary

Incorrect boundary conditions in the Internationalization component. This vulnerability was fixed in Firefox ESR 140.12, Firefox ESR 115.37, and Thunderbird 140.12.

Patch / fix

  • mozilla firefox 115.37.0, 140.12.0
  • mozilla thunderbird 140.12.0
  • firefox-esr Debian 12 140.12.0esr-1~deb12u1
  • firefox-esr Debian 13 140.12.0esr-1~deb13u1
  • firefox-esr Debian 14 140.12.0esr-1
  • thunderbird Debian 12 1:140.12.0esr-1~deb12u1
  • thunderbird Debian 13 1:140.12.0esr-1~deb13u1
  • thunderbird Debian 14 1:140.12.0esr-1

debian advisories DEBIAN-CVE-2026-12330

  • thunderbird RHEL 8 140.12.0-1.el8_10
  • thunderbird RHEL 10.2 140.12.0-1.el10_2
  • thunderbird RHEL 9 140.12.0-1.el9_8
  • firefox RHEL 9 140.12.0-1.el9_8
  • firefox-x11 RHEL 9 140.12.0-1.el9_8
  • firefox RHEL 10.2 140.12.0-1.el10_2
  • firefox RHEL 8 140.12.0-1.el8_10
  • thunderbird RHEL 9.2 E4S 140.12.0-1.el9_2

red hat advisories RHSA-2026:39706RHSA-2026:39428RHSA-2026:39142RHSA-2026:39141RHSA-2026:39011RHSA-2026:38751

  • MozillaFirefox SLES 16.0, SLES for SAP applications 16.0 140.13.0-160000.1.1
  • MozillaThunderbird SLE Workstation Extension 15 SP7, SLE Module for Package Hub 15 SP7 140.12.0-150200.8.277.1
  • MozillaFirefox SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +8 more 140.12.0-150200.152.245.1
  • MozillaFirefox SLES for SAP applications 16.0, SLES 16.0 140.12.0-160000.1.1
  • MozillaFirefox SLES LTSS Extended Security 12 SP5, SLES 12 SP5-LTSS 140.12.0-112.321.1

suse advisories SUSE-SU-2026:23115-1SUSE-SU-2026:23137-1SUSE-SU-2026:2852-1SUSE-SU-2026:2814-1SUSE-SU-2026:22351-1SUSE-SU-2026:2583-1

  • MozillaFirefox openSUSE Leap 16.0 140.13.0-160000.1.1
  • MozillaThunderbird openSUSE Leap 16.0 140.12.0-bp160.1.1
  • MozillaFirefox openSUSE Leap 16.0 140.12.0-160000.1.1
  • MozillaThunderbird openSUSE Tumbleweed 140.12.0-1.1
  • firefox-esr openSUSE Tumbleweed 140.12.0-1.1

opensuse advisories openSUSE-SU-2026:21519-1openSUSE-SU-2026:21168-1openSUSE-SU-2026:21043-1openSUSE-SU-2026:11072-1openSUSE-SU-2026:11055-1

  • thunderbird AlmaLinux 8 140.12.0-1.el8_10.alma.1
  • thunderbird AlmaLinux 10 140.12.0-1.el10_2.alma.1
  • thunderbird AlmaLinux 9 140.12.0-1.el9_8.alma.1
  • firefox AlmaLinux 8 140.12.0-1.el8_10.alma.1
  • firefox AlmaLinux 10 140.12.0-1.el10_2
  • firefox AlmaLinux 9 140.12.0-1.el9_8.alma.1
  • firefox-x11 AlmaLinux 9 140.12.0-1.el9_8.alma.1

almalinux advisories ALSA-2026:33445ALSA-2026:30846ALSA-2026:29940ALSA-2026:27717ALSA-2026:27733ALSA-2026:27734

  • thunderbird Rocky Linux 10 140.12.0-1.el10_2
  • thunderbird Rocky Linux 8 140.12.0-1.el8_10
  • thunderbird Rocky Linux 9 140.12.0-1.el9_8
  • firefox Rocky Linux 8 140.12.0-1.el8_10
  • firefox Rocky Linux 10 140.12.0-1.el10_2
  • firefox Rocky Linux 9 140.12.0-1.el9_8

rocky linux advisories RLSA-2026:30846RLSA-2026:33445RLSA-2026:29940RLSA-2026:27717RLSA-2026:27733RLSA-2026:27734

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-12330 updated cvss 6.1

firefox: thunderbird: Incorrect boundary conditions in the Internationalization component

  • Red Hat Enterprise Linux 6 firefox, thunderbird Red Hat Enterprise Linux 7 thunderbird
    affected: no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 10 rhel10/firefox-flatpak, rhel10/thunderbird-flatpak
    affected: no fix available
  • Red Hat Enterprise Linux AppStream (v. 8) firefox 140.12.0-1.el8_10, thunderbird 140.12.0-1.el8_10
    fixed: vendor fix RHSA-2026:27717
  • Red Hat Enterprise Linux AppStream (v. 9) firefox 140.12.0-1.el9_8, firefox-x11 140.12.0-1.el9_8, thunderbird 140.12.0-1.el9_8
    fixed: vendor fix RHSA-2026:27734
  • Red Hat Enterprise Linux AppStream (v. 10) firefox 140.12.0-1.el10_2, thunderbird 140.12.0-1.el10_2
    fixed: vendor fix RHSA-2026:27733
  • Red Hat Enterprise Linux AppStream AUS (v.8.4) firefox 140.12.0-1.el8_4, thunderbird 140.12.0-1.el8_4
    fixed: vendor fix RHSA-2026:36102
  • Red Hat Enterprise Linux AppStream AUS (v.8.6) firefox 140.12.0-1.el8_6, thunderbird 140.12.0-1.el8_6
    fixed: vendor fix RHSA-2026:37210
  • Red Hat Enterprise Linux AppStream E4S (v.8.8) firefox 140.12.0-1.el8_8, thunderbird 140.12.0-1.el8_8
    fixed: vendor fix RHSA-2026:36103
show 8 more
  • Red Hat Enterprise Linux AppStream E4S (v.9.2) firefox 140.12.0-1.el9_2, firefox-x11 140.12.0-1.el9_2, thunderbird 140.12.0-1.el9_2
    fixed: vendor fix RHSA-2026:36101
  • Red Hat Enterprise Linux AppStream E4S (v.9.4) firefox 140.12.0-1.el9_4, firefox-x11 140.12.0-1.el9_4, thunderbird 140.12.0-1.el9_4
    fixed: vendor fix RHSA-2026:39011
  • Red Hat Enterprise Linux AppStream EUS (v. 10.0) firefox 140.12.0-1.el10_0, thunderbird 140.12.0-1.el10_0
    fixed: vendor fix RHSA-2026:36100
  • Red Hat Enterprise Linux AppStream EUS (v.9.6) firefox 140.12.0-1.el9_6, firefox-x11 140.12.0-1.el9_6, thunderbird 140.12.0-1.el9_6
    fixed: vendor fix RHSA-2026:37391
  • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) firefox 140.12.0-1.el8_4, thunderbird 140.12.0-1.el8_4
    fixed: vendor fix RHSA-2026:36102
  • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) firefox 140.12.0-1.el8_6, thunderbird 140.12.0-1.el8_6
    fixed: vendor fix RHSA-2026:37210
  • Red Hat Enterprise Linux AppStream TUS (v.8.8) firefox 140.12.0-1.el8_8, thunderbird 140.12.0-1.el8_8
    fixed: vendor fix RHSA-2026:36103
  • Red Hat Enterprise Linux Server (v. 7 ELS) firefox 140.12.0-1.el7_9
    fixed: vendor fix RHSA-2026:38506

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
4 mo ago

Exploit prediction

0.16% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
CNA 3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

Affected products

  • Mozilla Firefox
  • Mozilla Thunderbird

Classification

Weakness
  • CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.