Possible WatchGuard Pre-Auth RCE via agent login XML-RPC CVE-2022-26318
- Category
- webserver
- Author
- HuntRule
- Published
- 2026-09-07
- Updated
- 2026-09-07
ATT&CK techniques
Initial Access → ExecutionRecon
Resource Dev
Initial Access
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects POST requests to the WatchGuard /agent/login endpoint that carry an XML-RPC agent.login method call. CVE-2022-26318 is a pre-authentication buffer overflow reached through an oversized gzip-encoded XML methodCall to this endpoint as shown by Assetnote, enabling remote code execution on the firewall.
Reporting behind it
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
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