Input validation flaw in Mozilla Firefox SVG component
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA.
Summary
Mozilla Firefox and Thunderbird before 159 contain an improper input validation flaw in the SVG component (CWE-20). A remote attacker without privileges can exploit it if a user interacts with crafted content, with high impact on confidentiality, integrity and availability.
Written with Claude Haiku 5.5 from the sources below · 2026-11-05
Description from the CNA
Other issue in the SVG component. This vulnerability was fixed in Firefox 159 and Thunderbird 159.
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 | — | 159 | Patch available | CNA |
| Mozilla | Thunderbird | — | 159 | Patch available | CNA |
Remediation
Update Mozilla Firefox to version 159 and Mozilla Thunderbird to version 159.
Written with Claude Haiku 5.5 from the sources below · 2026-11-05
- Fix · CNA Firefox (Mozilla) Fixed in 159
- Fix · CNA Thunderbird (Mozilla) Fixed in 159
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
Not affected: 5 products
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-27 Threatist record created from CVE-2026-118025
- 2026-10-27 Fix available: Mozilla/Thunderbird@159 · CNA
- 2026-10-27 1 new reference · CNA
- 2026-10-27 Alias added: GHSA-9h5j-68x4-pjqx
- 2026-11-03 Affected versions changed · Red Hat
- 2026-11-03 CVSS score added · Red Hat
- 2026-11-05 CVSS score added · CISA ADP
- 2026-11-05 Weakness changed · CISA ADP
- 2026-11-05 CISA SSVC decision points changed
- 2026-11-07 Priority changed: LOW → MEDIUM
References
More Mozilla 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-2026-118025 · CVE Program
- CVE-2026-118025 · NVD
- FIRST EPSS
- GHSA-9h5j-68x4-pjqx · GitHub Advisory Database · CC BY 4.0
- CVE-2026-118025 · 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