Invalid pointer in Mozilla Firefox and Thunderbird WebRender
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-824 and the CVSS impact.
Summary
Mozilla Firefox and Thunderbird contain an invalid pointer flaw in the Graphics: WebRender component, classified as access of an uninitialized pointer (CWE-824). A remote attacker without privileges or user interaction can cause high impact to confidentiality, integrity and availability.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
Description from the CNA
Invalid pointer in the Graphics: WebRender component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- 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 | — | 115.44, 153.6, 159 | Patch available | CNA |
| Mozilla | Thunderbird | — | 153.6, 159 | Patch available | CNA |
Remediation
Update Firefox to 115.44, 153.6 or 159 and Thunderbird to 153.6 or 159. The sources list no advisory identifiers for these fixes.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
- Fix · CNA Firefox (Mozilla) Fixed in 115.44, 153.6, 159
- Fix · CNA Thunderbird (Mozilla) Fixed in 153.6, 159
Timeline
- 2026-10-27 Threatist record created from CVE-2026-117917
- 2026-10-27 Fix available: Mozilla/Thunderbird@159 · CNA
- 2026-10-27 1 new reference · CNA
- 2026-10-27 Fix available: Mozilla/[email protected] · CNA
- 2026-10-27 1 new reference · CNA
- 2026-10-27 Alias added: GHSA-4grr-p8h7-vvx7
- 2026-11-04 CVSS score added · CISA ADP
- 2026-11-04 Weakness changed · CISA ADP
- 2026-11-04 CISA SSVC decision points changed
- 2026-11-04 Priority changed: LOW → MEDIUM
References
Other 6
- https://bugzilla.mozilla.org/show_bug.cgi?id=2079301
- https://www.mozilla.org/security/advisories/mfsa2026-118/
- https://www.mozilla.org/security/advisories/mfsa2026-119/
- https://www.mozilla.org/security/advisories/mfsa2026-120/
- https://www.mozilla.org/security/advisories/mfsa2026-121/
- https://www.mozilla.org/security/advisories/mfsa2026-122/
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-2026-117917 · CVE Program
- CVE-2026-117917 · NVD
- FIRST EPSS
- GHSA-4grr-p8h7-vvx7 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences