CVE-2025-36156
📋 TL;DR
A local attacker with access to specific files (CECSUB or CECRM) on IBM InfoSphere Data Replication VSAM for z/OS can exploit a stack-based buffer overflow to execute arbitrary code. This affects IBM InfoSphere Data Replication VSAM for z/OS Remote Source 11.4 installations where local file access is possible.
💻 Affected Systems
- IBM InfoSphere Data Replication VSAM for z/OS Remote Source
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with root/administrator privileges, allowing complete control over the z/OS system and potential lateral movement.
Likely Case
Local privilege escalation leading to unauthorized access to sensitive data and system resources within the z/OS environment.
If Mitigated
Limited impact due to strict file permissions and access controls preventing unauthorized local access to CECSUB/CECRM files.
🎯 Exploit Status
Requires local access and knowledge of file locations. Buffer overflow exploitation requires understanding of z/OS architecture.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Apply fix from IBM APAR IJ51207
Vendor Advisory: https://www.ibm.com/support/pages/node/7247224
Restart Required: Yes
Instructions:
1. Review IBM advisory. 2. Apply fix IJ51207 from IBM. 3. Restart affected services. 4. Verify patch application.
🔧 Temporary Workarounds
Restrict file permissions
z/OSLimit access to CECSUB and CECRM files to only necessary users
chmod 600 /path/to/CECSUB
chmod 600 /path/to/CECRM
Access control lists
z/OSImplement strict ACLs on container directories containing vulnerable files
🧯 If You Can't Patch
- Implement strict file system permissions on CECSUB and CECRM files
- Monitor access to these files and implement least privilege access controls
🔍 How to Verify
Check if Vulnerable:
Check if running IBM InfoSphere Data Replication VSAM for z/OS Remote Source 11.4 and verify file permissions on CECSUB/CECRM filesCheck Version:
Check product documentation for version verification commands specific to IBM InfoSphereVerify Fix Applied:
Verify patch IJ51207 is applied and check version information📡 Detection & Monitoring
Log Indicators:
- Unauthorized access attempts to CECSUB/CECRM files
- Abnormal process execution following file access
Network Indicators:
- Not applicable - local exploit only
SIEM Query:
Search for file access events to CECSUB or CECRM paths followed by unusual process execution