Fireware OS Pre-Authentication NULL Pointer Dereference Allows Remote Denial of Service
Priority MEDIUM 44CWE-476Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-476.
Summary
A NULL pointer dereference vulnerability in the WatchGuard Fireware OS authentication process allows a remote, unauthenticated attacker to crash the management daemon by sending a specially request to the login interface, resulting in a denial of service.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.004 34th percentileScored 2026-11-07
Fix Fixed Fireware OS (WatchGuard): 2026.3.2, 2026.2.3, 12.12.3 +1
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- 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 |
|---|---|---|---|---|---|
| WatchGuard | Fireware OS | 2026.3 to before 2026.3.2; 2025.0 to before 2026.2.3; 12.0 to before 12.12.3 | 2026.3.2, 2026.2.3, 12.12.3 | Patch available | CNA |
| WatchGuard | Fireware OS | 12.0 to before 12.5.21 | 12.5.21 | Patch available | CNA |
- Fireware OS VendorWatchGuard Affected 2026.3 to before 2026.3.2; 2025.0 to before 2026.2.3; 12.0 to before 12.12.3 Fixed in 2026.3.2, 2026.2.3, 12.12.3 Patch available CNA
- Fireware OS VendorWatchGuard Affected 12.0 to before 12.5.21 Fixed in 12.5.21 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:watchguard:fireware:*:*:*:*:*:*:*:* | 12.0 to before 12.5.21; 12.12 to before 12.12.3; 2025.0 to before 2026.2.3; 2026.3 to before 2026.3.2 | Vulnerable | WatchGuard |
- cpe:2.3:o:watchguard:fireware:*:*:*:*:*:*:*:* Versions 12.0 to before 12.5.21; 12.12 to before 12.12.3; 2025.0 to before 2026.2.3; 2026.3 to before 2026.3.2 Vulnerable ·WatchGuard
Remediation
- Fix · CNA Fireware OS (WatchGuard) Fixed in 2026.3.2, 2026.2.3, 12.12.3
- Fix · CNA Fireware OS (WatchGuard) Fixed in 12.5.21
Timeline
- 2026-10-02 Threatist record created from CVE-2026-86134
- 2026-10-03 Alias added: GHSA-fhvg-p495-phcg
- 2026-10-06 CVSS score added · NVD
References
More WatchGuard Fireware vulnerabilities
- TI-2022-09698 On WatchGuard Firebox and XTM appliances, an unauthenticated user can execute arbitrary… KEVCVSS 3.1CRITICAL 9.8
- TI-2025-13451 WatchGuard Firebox iked Out of Bounds Write Vulnerability KEVCVSS 4.0CRITICAL 9.3
- TI-2025-08474 WatchGuard Firebox iked Out of Bounds Write Vulnerability KEVCVSS 4.0CRITICAL 9.3
- TI-2022-07330 WatchGuard Firebox and XTM appliances allow a remote attacker with unprivileged… KEVCVSS 3.1HIGH 8.8
- TI-2013-05132 Buffer overflow in WGagent in WatchGuard WSM and Fireware before 11.8 allows remote… CVSS 2.0HIGH 9.3
- TI-2026-02885 WatchGuard Firebox Out of Bounds Write Vulnerability CVSS 4.0HIGH 8.6
Sources
- CVE-2026-86134 · CVE Program
- CVE-2026-86134 · NVD
- FIRST EPSS
- GHSA-fhvg-p495-phcg · 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