Detect CVE-2026-20045: Cisco Unified Communications Manager Code Injection in Sumo Logic CSE
Detects exploitation attempts targeting CVE-2026-20045, a code injection vulnerability (CWE-94) in Cisco Unified Communications Manager. This KEV-listed vulnerability allows remote attackers to inject and execute arbitrary code. Detection focuses on anomalous process execution, unexpected web shell activity, and suspicious outbound connections originating from CUCM processes.
MITRE ATT&CK
Sumo Detection Query
_sourceCategory=cisco/ucm OR _sourceCategory=cisco/callmanager OR _collector=cucm*
| parse "method=*" as method nodrop
| parse "uri=*" as uri nodrop
| parse "src_ip=*" as src_ip nodrop
| parse "process=*" as process nodrop
| parse "parent_process=*" as parent_process nodrop
| where (
(uri matches "*ccmadmin*" OR uri matches "*ccmservice*" OR uri matches "*axl*" OR uri matches "*cucm-uds*")
AND method = "POST"
)
OR (
parent_process matches "*java*" OR parent_process matches "*tomcat*"
AND (process matches "*bash*" OR process matches "*sh*" OR process matches "*python*" OR process matches "*curl*" OR process matches "*wget*")
)
| eval risk = if(parent_process matches "*java*" AND (process matches "*bash*" OR process matches "*sh*"), "CRITICAL",
if(uri matches "*axl*" AND method = "POST", "HIGH", "MEDIUM"))
| count by _sourceHost, src_ip, uri, process, parent_process, risk
| where _count > 0
| sort by risk, _count descSumo Logic query for detecting CVE-2026-20045 exploitation via anomalous CUCM API POSTs and shell process spawning under JVM processes on Cisco UCM hosts.
Data Sources
Required Tables
False Positives & Tuning
- Integration middleware platforms making large POST requests to AXL APIs
- Legitimate shell scripts invoked by Tomcat during upgrade procedures
- SolarWinds or other NMS tools polling UCM via HTTP
Other platforms for CVE-2026-20045
Testing Methodology
Validate this detection against 4 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 1CVE-2026-20045 Code Injection via AXL SOAP Endpoint
Expected signal: Tomcat access log entry showing POST to /axl/ with HTTP 200 or 500; if successful, process audit log showing command substitution execution under Tomcat user; /tmp/rce_test.txt created on CUCM host
- Test 2Simulate Java Spawning Reverse Shell on CUCM OS
Expected signal: ProcessRollup2 event (CrowdStrike) or DeviceProcessEvents (MDE) showing bash or java process with parent java; network connection to ATTACKER_IP:4444 if reverse shell variant used
- Test 3Web Shell Deployment Simulation on CUCM Tomcat
Expected signal: File creation event for .jsp file in /opt/cisco/platform/ui/; if Tomcat is running, subsequent HTTP GET requests to the new JSP path; audit log showing file write under test user account
- Test 4AXL Credential Brute-Force Reconnaissance
Expected signal: Multiple HTTP 401/403 responses from CUCM to the source IP in rapid succession; authentication failure events in CUCM security logs; CommonSecurityLog or Syslog entries showing repeated failed logins
Unlock Pro Content
Get the full detection package for CVE-2026-20045 including response playbook, investigation guide, and atomic red team tests.