Integer overflow in WatchGuard Fireware OS Access Portal
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- Code execution, Security bypass
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-190, CWE-288 and the CVSS impact.
Summary
WatchGuard Fireware OS from 2025.1 before 2026.4, from 12.0 before 12.12.4, and from 12.0 before 12.5.22 is affected. An integer overflow in WebSocket connection handling in the Access Portal (CWE-190) lets writes go past the bounds of a heap buffer. A remote unauthenticated attacker can trigger it with a specially crafted request while the Access Portal feature is enabled.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
Description from the CNA
An integer overflow vulnerability in the WebSocket connection handling used by WatchGuard Fireware OS's Access Portal allows a remote, unauthenticated attacker to write beyond the bounds of a heap buffer by sending a specially crafted request while the Access Portal feature is enabled.
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 |
|---|---|---|---|---|---|
| WatchGuard | Fireware OS | 2025.1 to before 2026.4; 12.0 to before 12.12.4 | 2026.4, 12.12.4 | Patch available | CNA |
| WatchGuard | Fireware OS | 12.0 to before 12.5.22 | 12.5.22 | Patch available | CNA |
- Fireware OS VendorWatchGuard Affected 2025.1 to before 2026.4; 12.0 to before 12.12.4 Fixed in 2026.4, 12.12.4 Patch available CNA
- Fireware OS VendorWatchGuard Affected 12.0 to before 12.5.22 Fixed in 12.5.22 Patch available CNA
CPE names Threatist (inferred) · 1
Inferred from how NVD named this product before; not given by a source.
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:watchguard:fireware:*:*:*:*:*:*:*:* | — | — | WatchGuard |
- cpe:2.3:o:watchguard:fireware:*:*:*:*:*:*:*:* Versions — — ·WatchGuard
Remediation
Fireware OS versions 2026.4, 12.12.4 and 12.5.22 fix this flaw. The sources do not list a vendor advisory for these fixes.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
- Fix · CNA Fireware OS (WatchGuard) Fixed in 2026.4, 12.12.4
- Fix · CNA Fireware OS (WatchGuard) Fixed in 12.5.22
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
WatchGuard Fireware OS 12.12.4, 2026.4
17 records Highest priority Priority MEDIUM 9 MEDIUM, 8 LOW
Other records, highest priority first
- TI-2026-81380 Fireware OS FireCluster Daemon Lacks Authentication, Allows Remote Root ActionsPriority MEDIUM 48
- TI-2026-81377 Stack buffer overflow in WatchGuard Fireware OS SIP proxyPriority MEDIUM 48
- TI-2026-81386 NULL pointer dereference in WatchGuard Fireware OS management loginPriority MEDIUM 44
- Release ·
WatchGuard Fireware OS 12.5.22
14 records Highest priority Priority MEDIUM 8 MEDIUM, 6 LOW
Other records, highest priority first
- TI-2026-81380 Fireware OS FireCluster Daemon Lacks Authentication, Allows Remote Root ActionsPriority MEDIUM 48
- TI-2026-81377 Stack buffer overflow in WatchGuard Fireware OS SIP proxyPriority MEDIUM 48
- TI-2026-81386 NULL pointer dereference in WatchGuard Fireware OS management loginPriority MEDIUM 44
Timeline
- 2026-10-27 Threatist record created from CVE-2026-93866
- 2026-10-27 Alias added: GHSA-g944-9gh9-2wqp
- 2026-11-04 CISA SSVC decision points changed
References
More WatchGuard 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-2023-19293 A DLL hijacking vulnerability in Panda Security VPN for Windows prior to version v15.14.8… CVSS 3.1MEDIUM 6.5
- TI-2015-04587 Watchguard XCS 9.2 and 10.0 before build 150522 allow remote authenticated users to… CVSS 2.0MEDIUM 6.5
Sources
- CVE-2026-93866 · CVE Program
- CVE-2026-93866 · NVD
- FIRST EPSS
- GHSA-g944-9gh9-2wqp · 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