Detect Apache Tomcat Missing Encryption of Sensitive Data (CVE-2026-34486) in IBM QRadar
Detects potential exploitation or exposure conditions related to CVE-2026-34486, an Apache Tomcat vulnerability (CWE-311: Missing Encryption of Sensitive Data) allowing sensitive data such as credentials, session identifiers, or configuration secrets to be transmitted or stored without adequate encryption. Actively exploited and listed in CISA KEV; associated with CISA BOD 26-04 prioritized remediation guidance. Detection focuses on plaintext transmission of Tomcat-managed credentials/session tokens over unencrypted channels, anomalous access to Tomcat configuration files (server.xml, context.xml, tomcat-users.xml, web.xml) containing sensitive data, and network indicators of cleartext protocol usage to Tomcat listener ports.
MITRE ATT&CK
QRadar Detection Query
SELECT sourceip, destinationip, destinationport, filename, username, starttime
FROM events
WHERE (filename ILIKE '%tomcat-users.xml%' OR filename ILIKE '%server.xml%' OR filename ILIKE '%context.xml%' OR filename ILIKE '%web.xml%')
OR (destinationport IN (8080,8009,80) AND applicationprotocol = 'HTTP' AND NOT applicationprotocol = 'HTTPS')
LAST 24 HOURS Flags QRadar events showing access to sensitive Tomcat configuration files or cleartext HTTP sessions to Tomcat service ports, indicative of missing-encryption exposure tied to CVE-2026-34486.
Data Sources
Required Tables
False Positives & Tuning
- Scheduled configuration audits by IT operations
- Load balancer health checks over plaintext HTTP to internal Tomcat nodes
- Vulnerability scanners intentionally probing cleartext ports
Other platforms for CVE-2026-34486
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 1Simulate cleartext credential exposure in tomcat-users.xml
Expected signal: File creation and read events for tomcat-users.xml containing plaintext credential strings
- Test 2Simulate cleartext HTTP request to Tomcat port
Expected signal: Network connection event to destination port 8080 using HTTP protocol without TLS
- Test 3Simulate access to Tomcat server.xml configuration file
Expected signal: DeviceProcessEvents/DeviceFileEvents showing PowerShell reading server.xml with connector definitions
- Test 4Simulate AJP cleartext connector probe
Expected signal: Network connection attempt logged to destination port 8009 (AJP) without TLS negotiation
References (4)
- https://lists.apache.org/thread/9510k5p5zdvt9pkkgtyp85mvwxo2qrly
- https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk
- https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk
- https://nvd.nist.gov/vuln/detail/CVE-2026-34486
Response Playbook
Triage
- Confirm the affected host is running Apache Tomcat and identify the version to verify it falls within scope of CVE-2026-34486 (missing encryption of sensitive data, CWE-311).
- Review Tomcat configuration files (server.xml, context.xml, tomcat-users.xml, web.xml) for cleartext credentials, session secrets, or connector definitions lacking SSL/TLS enforcement.
- Check network traffic logs for cleartext HTTP sessions on Tomcat listener ports (80, 8080, 8009/AJP) to determine if sensitive data was transmitted unencrypted.
- Correlate any alerts with CISA KEV status and BOD 26-04 prioritized remediation timelines to determine urgency of response.
Containment
- Enforce TLS on all Tomcat connectors (HTTP and AJP) and disable or restrict plaintext listeners to internal-only, firewalled segments.
- Rotate any credentials or session tokens discovered in plaintext configuration files or logs, including tomcat-users.xml entries.
Evidence Collection
- Preserve copies of Tomcat configuration files (server.xml, context.xml, tomcat-users.xml, web.xml) and access logs from the time window of suspected exposure.
- Capture network packet captures or flow logs showing cleartext sessions to/from the affected Tomcat instance for forensic review.
Escalation Criteria
- !Escalate to incident response if evidence shows sensitive credentials or session tokens were transmitted in cleartext and potentially intercepted by an unauthorized party.
- !Escalate to vulnerability management/patch teams if the Tomcat instance is internet-facing and unpatched, given active KEV exploitation status and BOD 26-04 mandated remediation deadlines.
Investigation Guide
Related Techniques
Forensic Artifacts
- >
Tomcat configuration files: server.xml, context.xml, tomcat-users.xml, web.xml - >
Tomcat access and catalina logs showing connector protocol usage and client IPs - >
Network flow/packet capture data showing cleartext HTTP or AJP sessions to Tomcat ports
Tuning Guidance
Baseline expected administrative access patterns to Tomcat configuration files (who, when, from where) to reduce noise from legitimate config management. Exclude known internal load balancers or health-check sources that intentionally use cleartext HTTP within segmented, low-risk network zones. Increase confidence when config file access is followed closely by outbound network connections or when the host is internet-facing.
Hunting Queries
Hunts for recent modifications to Tomcat configuration files and repeated cleartext HTTP access patterns that may indicate reconnaissance or active exploitation of the missing-encryption weakness.
DeviceFileEvents
| where FileName in~ ("tomcat-users.xml","server.xml","context.xml","web.xml")
| where ActionType in ("FileModified","FileCreated")
| project TimeGenerated, DeviceName, FileName, InitiatingProcessAccountName index=* sourcetype=tomcat_access
| search "http://" AND ("8080" OR "8009")
| stats count by host, uri, clientip
| sort -count Atomic Red Team Tests
Creates a test tomcat-users.xml file containing a plaintext password to simulate the missing-encryption condition described in CVE-2026-34486.
Command
mkdir -p /tmp/atomic-tomcat && printf '<tomcat-users>\n <user username="testadmin" password="PlaintextPass123" roles="manager-gui"/>\n</tomcat-users>' > /tmp/atomic-tomcat/tomcat-users.xml && cat /tmp/atomic-tomcat/tomcat-users.xml Cleanup
rm -rf /tmp/atomic-tomcat Expected Telemetry
File creation and read events for tomcat-users.xml containing plaintext credential strings
Expected Detection
KQL/SPL rule flags process access to tomcat-users.xml with sensitive keyword match
Sends an HTTP (non-TLS) request to a local test listener on port 8080 to simulate cleartext transmission to a Tomcat connector.
Command
python3 -m http.server 8080 --bind 127.0.0.1 & sleep 1; curl -s http://127.0.0.1:8080/manager/html -o /dev/null; kill %1 Cleanup
pkill -f 'http.server 8080' || true Expected Telemetry
Network connection event to destination port 8080 using HTTP protocol without TLS
Expected Detection
EQL/QRadar rule flags cleartext HTTP session to Tomcat listener port
Reads a mock server.xml file to simulate an attacker or insider accessing Tomcat connector configuration that may lack SSL enforcement.
Command
New-Item -Path $env:TEMP\server.xml -ItemType File -Value '<Server><Connector port="8080" protocol="HTTP/1.1"/></Server>' -Force; Get-Content $env:TEMP\server.xml Cleanup
Remove-Item $env:TEMP\server.xml -Force Expected Telemetry
DeviceProcessEvents/DeviceFileEvents showing PowerShell reading server.xml with connector definitions
Expected Detection
KQL rule flags process command line referencing server.xml file access
Attempts a raw TCP connection to port 8009 (AJP) to simulate probing of an unencrypted Tomcat AJP connector, a known vector for missing-encryption exposure.
Command
nc -zv 127.0.0.1 8009 Cleanup
true Expected Telemetry
Network connection attempt logged to destination port 8009 (AJP) without TLS negotiation
Expected Detection
Chronicle/CrowdStrike rule flags network connection to AJP port 8009