Out-of-bounds write in Mozilla Firefox
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- Partial Red Hat: 14 fixed, 4 without a fix
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat.
Summary
Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 115.18, Firefox ESR 128.5, Thunderbird 115.18, and Thunderbird 128.5. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Firefox ESR 115.19, Thunderbird 134, and Thunderbird 128.6.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
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 | — | 115.19, 128.6, 134 | Patch available | CNA |
| Mozilla | Thunderbird | — | 128.6, 134 | Patch available | CNA |
- Firefox VendorMozilla Affected — Fixed in 115.19, 128.6, 134 Patch available CNA
- Thunderbird VendorMozilla Affected — Fixed in 128.6, 134 Patch available CNA
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:* | up to 115.19.0 | Vulnerable | Mozilla |
| cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* | before 134.0 | Vulnerable | Mozilla |
| cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:* | 116.0 to before 128.6.0 | Vulnerable | Mozilla |
| cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* | before 128.6.0; 129.0 to before 134.0 | Vulnerable | Mozilla |
- cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:* Versions up to 115.19.0 Vulnerable ·Mozilla
- cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* Versions before 134.0 Vulnerable ·Mozilla
- cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:* Versions 116.0 to before 128.6.0 Vulnerable ·Mozilla
- cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions before 128.6.0; 129.0 to before 134.0 Vulnerable ·Mozilla
Remediation
- Fix · CNA Firefox (Mozilla) Fixed in 115.19, 128.6, 134
- Fix · CNA Thunderbird (Mozilla) Fixed in 128.6, 134
Red Hat 19 advisories
- RHSA-2025:0286 Released 2025-01-13 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream AUS (v. 8.2) thunderbird-128.6.0-3.el8_2
- RHSA-2025:0287 Released 2025-01-13 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream AUS (v.8.4) thunderbird-128.6.0-3.el8_4
- Red Hat Enterprise Linux AppStream E4S (v.8.4) thunderbird-128.6.0-3.el8_4
- Red Hat Enterprise Linux AppStream TUS (v.8.4) thunderbird-128.6.0-3.el8_4
- RHSA-2025:0284 Released 2025-01-13 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream EUS (v.8.8) thunderbird-128.6.0-3.el8_8
Show 16 more Red Hat advisories
- RHSA-2025:0281 Released 2025-01-13 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream (v. 8) thunderbird-128.6.0-3.el8_10
- RHSA-2025:0275 Released 2025-01-13 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream AUS (v.8.6) thunderbird-128.6.0-3.el8_6
- Red Hat Enterprise Linux AppStream E4S (v.8.6) thunderbird-128.6.0-3.el8_6
- Red Hat Enterprise Linux AppStream TUS (v.8.6) thunderbird-128.6.0-3.el8_6
- RHSA-2025:0167 Released 2025-01-09 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream EUS (v.9.2) thunderbird-128.6.0-3.el9_2
- RHSA-2025:0166 Released 2025-01-09 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream EUS (v.9.4) thunderbird-128.6.0-3.el9_4
- RHSA-2025:0165 Released 2025-01-09 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream E4S (v.9.0) thunderbird-128.6.0-3.el9_0
- RHSA-2025:0162 Released 2025-01-09 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream E4S (v.9.0) firefox-128.6.0-1.el9_0
- RHSA-2025:0144 Released 2025-01-09 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream (v. 8) firefox-128.6.0-1.el8_10
- RHSA-2025:0147 Released 2025-01-09 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream (v. 9) thunderbird-128.6.0-3.el9_5
- RHSA-2025:0137 Released 2025-01-09 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream EUS (v.8.8) firefox-128.6.0-1.el8_8
- RHSA-2025:0138 Released 2025-01-09 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream EUS (v.9.2) firefox-128.6.0-1.el9_2, firefox-x11-128.6.0-1.el9_2
- RHSA-2025:0136 Released 2025-01-09 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream AUS (v.8.6) firefox-128.6.0-1.el8_6
- Red Hat Enterprise Linux AppStream E4S (v.8.6) firefox-128.6.0-1.el8_6
- Red Hat Enterprise Linux AppStream TUS (v.8.6) firefox-128.6.0-1.el8_6
- RHSA-2025:0132 Released 2025-01-09 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux Server (v. 7 ELS) firefox-128.6.0-1.el7_9
- RHSA-2025:0135 Released 2025-01-09 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream EUS (v.9.4) firefox-128.6.0-1.el9_4, firefox-x11-128.6.0-1.el9_4
- RHSA-2025:0134 Released 2025-01-09 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream AUS (v.8.4) firefox-128.6.0-1.el8_4
- Red Hat Enterprise Linux AppStream E4S (v.8.4) firefox-128.6.0-1.el8_4
- Red Hat Enterprise Linux AppStream TUS (v.8.4) firefox-128.6.0-1.el8_4
- RHSA-2025:0133 Released 2025-01-09 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream AUS (v. 8.2) firefox-128.6.0-1.el8_2
- RHSA-2025:0080 Released 2025-01-08 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream (v. 9) firefox-128.6.0-1.el9_5, firefox-x11-128.6.0-1.el9_5
Vendor assessments
Red Hat
Red Hat rating: Important. 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 9 | Affected | No fix yet |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2025:0144, RHSA-2025:0281 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2025:0080, RHSA-2025:0147 |
| Red Hat Enterprise Linux AppStream AUS (v. 8.2) | Fixed | RHSA-2025:0133, RHSA-2025:0286 |
| Red Hat Enterprise Linux AppStream AUS (v.8.4) | Fixed | RHSA-2025:0134, RHSA-2025:0287 |
| Red Hat Enterprise Linux AppStream AUS (v.8.6) | Fixed | RHSA-2025:0136, RHSA-2025:0275 |
| Red Hat Enterprise Linux AppStream E4S (v.8.4) | Fixed | RHSA-2025:0134, RHSA-2025:0287 |
| Red Hat Enterprise Linux AppStream E4S (v.8.6) | Fixed | RHSA-2025:0136, RHSA-2025:0275 |
| Red Hat Enterprise Linux AppStream E4S (v.9.0) | Fixed | RHSA-2025:0162, RHSA-2025:0165 |
| Red Hat Enterprise Linux AppStream EUS (v.8.8) | Fixed | RHSA-2025:0137, RHSA-2025:0284 |
| Red Hat Enterprise Linux AppStream EUS (v.9.2) | Fixed | RHSA-2025:0138, RHSA-2025:0167 |
| Red Hat Enterprise Linux AppStream EUS (v.9.4) | Fixed | RHSA-2025:0135, RHSA-2025:0166 |
| Red Hat Enterprise Linux AppStream TUS (v.8.4) | Fixed | RHSA-2025:0134, RHSA-2025:0287 |
| Red Hat Enterprise Linux AppStream TUS (v.8.6) | Fixed | RHSA-2025:0136, RHSA-2025:0275 |
| Red Hat Enterprise Linux Server (v. 7 ELS) | Fixed | RHSA-2025:0132 |
Timeline
- 2026-10-02 Threatist record created from CVE-2025-0242
- 2026-10-03 Alias added: GHSA-qw28-p6qx-vj78
References
Advisory 5
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-2025-0242 · CVE Program
- CVE-2025-0242 · NVD
- FIRST EPSS
- GHSA-qw28-p6qx-vj78 · GitHub Advisory Database · CC BY 4.0
- CVE-2025-0242 · 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