Detect Linux Kernel Incorrect Resource Transfer Between Spheres (CVE-2026-31431) in IBM QRadar
CVE-2026-31431 is a Linux Kernel vulnerability classified as CWE-669 (Incorrect Resource Transfer Between Spheres). The flaw allows improper transfer of resources across security boundaries within the kernel, potentially enabling privilege escalation or unauthorized memory access. This vulnerability is listed in the CISA Known Exploited Vulnerabilities catalog, indicating active exploitation in the wild. Attackers with local access may exploit this to escalate privileges to root or escape container boundaries.
MITRE ATT&CK
QRadar Detection Query
SELECT DATEFORMAT(starttime,'YYYY-MM-dd HH:mm:ss') AS 'Event Time', sourceip AS 'Source IP', username AS 'Username', QIDNAME(qid) AS 'Event Name', LOGSOURCENAME(logsourceid) AS 'Log Source', UTF8(payload) AS 'Raw Event'
FROM events
WHERE LOGSOURCETYPENAME(devicetype) IN ('Linux OS', 'Syslog', 'Linux Audit')
AND (UTF8(payload) ILIKE '%copy_to_user%'
OR UTF8(payload) ILIKE '%copy_from_user%'
OR UTF8(payload) ILIKE '%__copy_overflow%'
OR UTF8(payload) ILIKE '%general protection fault%'
OR UTF8(payload) ILIKE '%use-after-free%'
OR UTF8(payload) ILIKE '%kernel NULL pointer dereference%'
OR UTF8(payload) ILIKE '%BUG: unable to handle%')
AND starttime > NOW() - 604800000
ORDER BY starttime DESC
LIMIT 1000QRadar AQL query detecting Linux kernel anomalies consistent with CVE-2026-31431 resource transfer boundary violations, searching kernel log payloads for copy function faults and memory boundary errors.
Data Sources
Required Tables
False Positives & Tuning
- Kernel OOPS messages from hardware memory errors unrelated to exploitation attempts
- Automated Linux kernel security scanning tools that generate controlled fault conditions
- High-availability systems with kernel watchdogs that produce periodic diagnostic messages
Other platforms for CVE-2026-31431
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 1Simulate kernel copy boundary fault via /proc/kcore read attempt
Expected signal: Kernel message in dmesg showing access denial or fault; audit log SYSCALL record for 'open' or 'read' on /proc/kcore by non-root UID; possible kernel warning message about unauthorized memory access attempt
- Test 2Privilege escalation simulation via SUID binary abuse on unpatched kernel
Expected signal: Audit log SYSCALL record showing execve of test_suid with uid!=0 but euid=0; EDR process event showing SUID execution; possible AppArmor/SELinux denial log if MAC policy is enforced
- Test 3Container escape boundary test via /proc/sysrq-trigger probe
Expected signal: Host kernel log entries showing container namespace probe attempts; Docker daemon log entries for the test container; audit log entries showing file access attempts to /dev/mem or /proc/1/ from container process
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