CVE-2026-103594
Fireware OS Stack Buffer Overflow in WireGuard Configuration Allows Remote Code Execution
CVE-2026-103594 is a critical vulnerability (CVSS 9.5) in Watchguard Fireware Os, published October 27, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.43%, the 38th percentile. No source names a fixed version.
- Severity
- 9.5 CriticalCVSS 4.0, CVE List
- Exploit chance
- 0.43%EPSS, 38th percentile
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
- No fix listedNo source names one
Description
A stack-based buffer overflow vulnerability in Fireware OS's WireGuard configuration processing allows a remote attacker that has man-in-the-middle TLS-decrypted access between the Firebox and WatchGuard Cloud to create a Denial of Service condition and potentially execute arbitrary code by tampering with a FireCloud Gateway configuration payload.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
Affected products
What each source reports
CVE List Score used
Fireware OS Stack Buffer Overflow in WireGuard Configuration Allows Remote Code Execution
A stack-based buffer overflow vulnerability in Fireware OS's WireGuard configuration processing allows a remote attacker that has man-in-the-middle TLS-decrypted access between the Firebox and WatchGuard Cloud to create a Denial of Service condition and potentially execute arbitrary code by tampering with a FireCloud Gateway configuration payload.
- Record
CVE-2026-103594- CVSS 4.0
- 9.5 Critical
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - Weakness
- CWE-121, CWE-1284, CWE-787
- Updated
- 2026-11-04
EUVDEUVD-2026-111159
A stack-based buffer overflow vulnerability in Fireware OS's WireGuard configuration processing allows a remote attacker that has man-in-the-middle TLS-decrypted access between the Firebox and WatchGuard Cloud to create a Denial of Service condition and potentially execute arbitrary code by tampering with a FireCloud Gateway configuration payload.
- Record
EUVD-2026-111159- CVSS 4.0
- 9.5 Critical
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - Updated
- 2026-11-04
GitHub AdvisoriesGHSA-69hq-vhp9-m5w6
A stack-based buffer overflow vulnerability in Fireware OS's WireGuard configuration processing...
A stack-based buffer overflow vulnerability in Fireware OS's WireGuard configuration processing allows a remote attacker that has man-in-the-middle TLS-decrypted access between the Firebox and WatchGuard Cloud to create a Denial of Service condition and potentially execute arbitrary code by tampering with a FireCloud Gateway configuration payload.
- Record
GHSA-69hq-vhp9-m5w6- CVSS 4.0
- 9.5 Critical
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-121
- Updated
- 2026-11-02
NVD
A stack-based buffer overflow vulnerability in Fireware OS's WireGuard configuration processing allows a remote attacker that has man-in-the-middle TLS-decrypted access between the Firebox and WatchGuard Cloud to create a Denial of Service condition and potentially execute arbitrary code by tampering with a FireCloud Gateway configuration payload.
- Record
CVE-2026-103594- CVSS 4.0
- 9.5 Critical
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-121, CWE-787, CWE-1284
- Updated
- 2026-11-04
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | CVE List, EUVD | |
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.