Memory corruption in Mozilla Firefox
Priority LOW 24CWE-119Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- Partial Red Hat: 14 fixed, 3 without a fix
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat.
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00164 5th percentileScored 2026-11-07
Fix Partial Firefox (Mozilla): 115.37, 140.12Thunderbird (Mozilla): 140.12Red Hat: 21 advisoriesRed Hat: 14 fixed, 3 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Mozilla | Firefox | — | 115.37, 140.12 | Patch available | CNA |
| Mozilla | Thunderbird | — | 140.12 | Patch available | CNA |
Remediation
- Fix · CNA Firefox (Mozilla) Fixed in 115.37, 140.12
- Fix · CNA Thunderbird (Mozilla) Fixed in 140.12
Red Hat 21 advisories
- RHSA-2026:39706 Released 2026-07-15 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream E4S (v.9.2) thunderbird-140.12.0-1.el9_2
- RHSA-2026:39428 Released 2026-07-14 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream AUS (v.8.4) thunderbird-140.12.0-1.el8_4
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) thunderbird-140.12.0-1.el8_4
- RHSA-2026:39142 Released 2026-07-14 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream E4S (v.8.8) thunderbird-140.12.0-1.el8_8
- Red Hat Enterprise Linux AppStream TUS (v.8.8) thunderbird-140.12.0-1.el8_8
Show 18 more Red Hat advisories
- RHSA-2026:39141 Released 2026-07-14 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream AUS (v.8.6) thunderbird-140.12.0-1.el8_6
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) thunderbird-140.12.0-1.el8_6
- RHSA-2026:39011 Released 2026-07-13 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream E4S (v.9.4) firefox-140.12.0-1.el9_4, firefox-x11-140.12.0-1.el9_4
- RHSA-2026:38750 Released 2026-07-13 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream EUS (v.9.6) thunderbird-140.12.0-1.el9_6
- RHSA-2026:38753 Released 2026-07-13 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream E4S (v.9.4) thunderbird-140.12.0-1.el9_4
- RHSA-2026:38751 Released 2026-07-13 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream EUS (v. 10.0) thunderbird-140.12.0-1.el10_0
- RHSA-2026:38506 Released 2026-07-13 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux Server (v. 7 ELS) firefox-140.12.0-1.el7_9
- RHSA-2026:37391 Released 2026-07-09 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream EUS (v.9.6) firefox-140.12.0-1.el9_6, firefox-x11-140.12.0-1.el9_6
- RHSA-2026:37210 Released 2026-07-09 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream AUS (v.8.6) firefox-140.12.0-1.el8_6
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) firefox-140.12.0-1.el8_6
- RHSA-2026:36101 Released 2026-07-07 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream E4S (v.9.2) firefox-140.12.0-1.el9_2, firefox-x11-140.12.0-1.el9_2
- RHSA-2026:36103 Released 2026-07-07 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream E4S (v.8.8) firefox-140.12.0-1.el8_8
- Red Hat Enterprise Linux AppStream TUS (v.8.8) firefox-140.12.0-1.el8_8
- RHSA-2026:36102 Released 2026-07-07 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream AUS (v.8.4) firefox-140.12.0-1.el8_4
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) firefox-140.12.0-1.el8_4
- RHSA-2026:36100 Released 2026-07-07 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream EUS (v. 10.0) firefox-140.12.0-1.el10_0
- RHSA-2026:33445 Released 2026-06-30 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream (v. 8) thunderbird-140.12.0-1.el8_10
- RHSA-2026:30846 Released 2026-06-29 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream (v. 10) thunderbird-140.12.0-1.el10_2
- RHSA-2026:29940 Released 2026-06-25 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream (v. 9) thunderbird-140.12.0-1.el9_8
- RHSA-2026:27734 Released 2026-06-22 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream (v. 9) firefox-140.12.0-1.el9_8, firefox-x11-140.12.0-1.el9_8
- RHSA-2026:27733 Released 2026-06-22 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream (v. 10) firefox-140.12.0-1.el10_2
- RHSA-2026:27717 Released 2026-06-22 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream (v. 8) firefox-140.12.0-1.el8_10
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2026:27733, RHSA-2026:30846 |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2026:27717, RHSA-2026:33445 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2026:27734, RHSA-2026:29940 |
| Red Hat Enterprise Linux AppStream AUS (v.8.4) | Fixed | RHSA-2026:36102, RHSA-2026:39428 |
| Red Hat Enterprise Linux AppStream AUS (v.8.6) | Fixed | RHSA-2026:37210, RHSA-2026:39141 |
| Red Hat Enterprise Linux AppStream E4S (v.8.8) | Fixed | RHSA-2026:36103, RHSA-2026:39142 |
| Red Hat Enterprise Linux AppStream E4S (v.9.2) | Fixed | RHSA-2026:36101, RHSA-2026:39706 |
| Red Hat Enterprise Linux AppStream E4S (v.9.4) | Fixed | RHSA-2026:38753, RHSA-2026:39011 |
| Red Hat Enterprise Linux AppStream EUS (v. 10.0) | Fixed | RHSA-2026:36100, RHSA-2026:38751 |
| Red Hat Enterprise Linux AppStream EUS (v.9.6) | Fixed | RHSA-2026:37391, RHSA-2026:38750 |
| Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) | Fixed | RHSA-2026:36102, RHSA-2026:39428 |
| Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) | Fixed | RHSA-2026:37210, RHSA-2026:39141 |
| Red Hat Enterprise Linux AppStream TUS (v.8.8) | Fixed | RHSA-2026:36103, RHSA-2026:39142 |
| Red Hat Enterprise Linux Server (v. 7 ELS) | Fixed | RHSA-2026:38506 |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-12330
- 2026-10-03 Alias added: GHSA-jrcp-wwfg-qhjg
- 2026-11-06 Fix available: RHSA-2026:27733 · Red Hat
References
More Mozilla Firefox vulnerabilities
- TI-2024-08981 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.8
- TI-2022-09832 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.6
- TI-2019-08769 Improper input validation in Mozilla Firefox ESR KEVCVSS 3.1CRITICAL 10.0
- TI-2010-03577 Mozilla Firefox 3.5.x through 3.5.14 and 3.6.x through 3.6.11, Thunderbird 3.1.6 before… KEVCVSS 3.1CRITICAL 9.8
- TI-2023-04799 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
- TI-2023-04477 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
Sources
- CVE-2026-12330 · CVE Program
- CVE-2026-12330 · NVD
- FIRST EPSS
- GHSA-jrcp-wwfg-qhjg · GitHub Advisory Database · CC BY 4.0
- CVE-2026-12330 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences