High severity · published Aug 27, 2026
CVE-2026-78008
Fireware OS Authenticated Buffer Overflow in wgagent
8.6
CVSS
0.6%
EPSS
No
On KEV
Description
A buffer overflow vulnerability in the WatchGuard Fireware OS Management Web UI allows an authenticated administrator with network access to cause a denial of service (DoS) condition or potentially execute arbitrary code by sending specially crafted network traffic.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
Fireware OS · WatchGuard
2025.0 before 2026.2.2; 12.0 before 12.12.2; 2026.3 before 2026.3.1; 12.0 before 12.5.20 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-78008
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-78008
psirt.watchguard.com
https://psirt.watchguard.com/CVE-2026-78008
More from Fireware OS
9.8
CVE-2025-14733
WatchGuard Firebox iked Out of Bounds Write Vulnerability
9.8
CVE-2025-9242
WatchGuard Firebox iked Out of Bounds Write Vulnerability
9.8
CVE-2026-86131
Fireware OS Code Injection in BOVPN Over TLS Client Allows Remote Code Execution
9.5
CVE-2026-103594
Fireware OS Stack Buffer Overflow in WireGuard Configuration Allows Remote Code Execution
9.4
CVE-2026-90465
Fireware OS Missing Authentication in FireCluster Sync Allows Privilege Escalation