Possible RD Web Access Brute Force via Repeated Login POST Requests

ATT&CK techniques

Initial Access → Cred Access

Recon
Resource Dev
Initial Access
- T1133External Remote Services
Execution
Persistence
- T1133External Remote Services
Priv Esc
Defense Evasion
Cred Access
- T1110.003Password Spraying
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects HTTP POST requests to the Remote Desktop Web Access login endpoint, matching the RDWeb brute-force activity observed in a terminal server phishing intrusion. Adversaries automate large volumes of credential guesses against the RDWeb form where an HTTP 302 response indicates a successful authentication. High-volume POSTs to this endpoint signal password guessing against externally exposed remote access.

Reporting behind it

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Possible RD Web Access Brute Force via Repeated Login POST Requests

Pivot detection · T1110.003 · 9 related

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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