CVE-2025-3631
📋 TL;DR
A use-after-free vulnerability (CWE-416) in IBM MQ 9.3 and 9.4 allows a malicious client to crash the AMQRMPPA channel process via SIGSEGV when connecting to a queue manager. This affects IBM MQ queue managers running vulnerable versions, potentially disrupting message processing services.
💻 Affected Systems
- IBM MQ
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Denial of service causing complete disruption of IBM MQ message processing, affecting dependent applications and business operations.
Likely Case
Intermittent channel process crashes leading to message processing delays and service instability.
If Mitigated
Minimal impact with proper network segmentation and client authentication controls limiting attack surface.
🎯 Exploit Status
Exploitation requires client access to queue manager. No authentication bypass needed beyond normal client credentials.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Apply fix packs as specified in IBM advisories
Vendor Advisory: https://www.ibm.com/support/pages/node/7237025
Restart Required: Yes
Instructions:
1. Review IBM advisory for specific fix pack requirements. 2. Apply appropriate fix pack for your version. 3. Restart queue manager and channel processes. 4. Verify fix application.
🔧 Temporary Workarounds
Restrict Client Access
allLimit which clients can connect to vulnerable queue managers using MQ authentication and authorization controls.
ALTER QMGR CHLAUTH(DISABLED)
SET CHLAUTH('*') TYPE(BLOCKUSER) USERLIST('*NOACCESS')
SET CHLAUTH('*') TYPE(ADDRESSMAP) ADDRESS('*') USERSRC(NOACCESS)
Monitor and Restart Channels
allImplement monitoring for AMQRMPPA channel crashes with automated restart procedures.
strmqm -x QMNAME
runmqsc QMNAME <<< 'START CHANNEL(CHANNELNAME)'
🧯 If You Can't Patch
- Implement strict network segmentation to limit client access to queue managers
- Enforce strong client authentication and authorization controls
🔍 How to Verify
Check if Vulnerable:
Check IBM MQ version using 'dspmqver' command and compare against affected versions 9.3.x and 9.4.xCheck Version:
dspmqverVerify Fix Applied:
Verify fix pack installation using 'dspmqver' and confirm version includes required fixes. Monitor AMQRMPPA channel stability.📡 Detection & Monitoring
Log Indicators:
- AMQRMPPA process termination messages
- SIGSEGV errors in MQ error logs
- Channel status changes to INACTIVE or RETRYING
Network Indicators:
- Multiple connection attempts from single client followed by channel disruption
- Unusual client connection patterns to AMQRMPPA ports
SIEM Query:
source="mq_error.log" AND ("SIGSEGV" OR "AMQRMPPA" AND "terminated")