Detect CVE-2025-14733: WatchGuard Firebox Out-of-Bounds Write Exploitation in Elastic Security
Detects exploitation attempts targeting CVE-2025-14733, an out-of-bounds write vulnerability (CWE-787) in WatchGuard Firebox devices. This vulnerability is actively exploited in the wild (CISA KEV) and may allow remote code execution or device compromise. Detection focuses on anomalous management interface activity, unexpected process crashes, and network indicators consistent with exploitation.
MITRE ATT&CK
- Tactic
- Initial Access Execution Impact
Elastic Detection Query
sequence by host.name with maxspan=10m
[network where event.type == "connection" and
(destination.port == 4117 or destination.port == 4118 or destination.port == 8080 or destination.port == 443) and
(
network.application == "watchguard" or
host.name like~ "*firebox*" or
host.name like~ "*watchguard*"
)
] with runs=50
[process where event.type == "end" and event.action == "process_stopped" and
(
process.name like~ "wgagent" or
process.name like~ "wgrd" or
process.name like~ "wguard" or
process.name like~ "httpd"
) and
process.exit_code != 0
]Correlates high-volume network connections to WatchGuard management ports followed by unexpected process termination, indicating potential CVE-2025-14733 exploitation triggering an out-of-bounds write crash.
Data Sources
Required Tables
False Positives & Tuning
- Planned maintenance causing process restarts coinciding with high network activity
- Automated monitoring tools generating connection spikes before scheduled device reboots
- Firmware updates causing service restarts with non-zero exit codes
- Legitimate bulk administrative operations from management systems
Other platforms for CVE-2025-14733
Testing Methodology
Validate this detection against 3 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.
- Test 1Simulate WatchGuard Management Interface Reconnaissance
Expected signal: Network connection logs showing SYN packets to ports 4117, 4118, 8080, and 443 from the attacker IP; IDS alerts on service enumeration; Firebox access logs showing connection attempts
- Test 2Malformed HTTP Request to Firebox Management Interface
Expected signal: Firebox crash or exception log entries; process termination events for web management daemon; syslog SIGSEGV or abnormal exit entries; network connection termination without proper HTTP response
- Test 3Post-Exploitation: Simulate Unauthorized Admin Account Creation Check
Expected signal: WatchGuard audit log entry for admin account creation; API access logs showing POST to user management endpoint; SIEM alert on privileged account creation on network device
Unlock Pro Content
Get the full detection package for CVE-2025-14733 including response playbook, investigation guide, and atomic red team tests.