Detect Rockwell Automation Logix Controllers Insufficient Credential Protection (CVE-2021-22681) in IBM QRadar
CVE-2021-22681 is an insufficient protection of credentials vulnerability (CWE-522) affecting Rockwell Automation multiple products including Logix controllers. An attacker can intercept or obtain weakly protected credentials used to authenticate with Logix controllers, enabling authentication bypass. This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog and poses critical risk in OT/ICS environments where unauthorized controller access could cause process disruption or physical damage.
MITRE ATT&CK
QRadar Detection Query
SELECT sourceip, destinationip, destinationport, "protocolname", DATEFORMAT(starttime, 'yyyy-MM-dd HH:mm:ss') AS event_time, username, "devicetype", logsourcename(logsourceid) AS log_source, UTF8(payload) AS raw_payload
FROM events
WHERE (destinationport IN (44818, 2222, 2221) OR "protocolname" ILIKE '%EtherNet%' OR "protocolname" ILIKE '%CIP%')
AND (logsourcename(logsourceid) ILIKE '%rockwell%' OR logsourcename(logsourceid) ILIKE '%logix%' OR logsourcename(logsourceid) ILIKE '%claroty%' OR logsourcename(logsourceid) ILIKE '%nozomi%' OR UTF8(payload) ILIKE '%logix%' OR UTF8(payload) ILIKE '%ControlLogix%')
AND LAST 7 DAYS
ORDER BY starttime DESC
LIMIT 1000QRadar AQL query to identify EtherNet/IP and CIP protocol traffic targeting Rockwell Logix controllers, supporting investigation of CVE-2021-22681 credential interception activity.
Data Sources
Required Tables
False Positives & Tuning
- Authorized PLC programming sessions from known engineering workstations
- Scheduled controller backup operations
- ICS historian data collection from Logix controllers
Other platforms for CVE-2021-22681
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 1EtherNet/IP Controller Enumeration via nmap
Expected signal: Network connection events from the scanning host to port 44818 on multiple destination IPs; IDS alerts for CIP/EtherNet/IP enumeration
- Test 2CIP Session Credential Capture via Wireshark
Expected signal: Passive capture produces no active network events; detection depends on promiscuous mode detection or IDS passive analysis alerts
- Test 3RSLinx Classic Unauthorized Connection Attempt
Expected signal: Windows process creation for RSLinx.exe; network connection from non-engineering workstation to controller port 44818; controller audit log entry for unauthorized connection attempt
Unlock Pro Content
Get the full detection package for CVE-2021-22681 including response playbook, investigation guide, and atomic red team tests.