CVE-2024-26289
📋 TL;DR
CVE-2024-26289 is a critical deserialization vulnerability in PMB Services PMB that allows remote attackers to execute arbitrary code by sending malicious serialized data. This affects PMB installations running vulnerable versions, potentially compromising the entire system. Organizations using affected PMB versions for library management or similar functions are at risk.
💻 Affected Systems
- PMB Services PMB
📦 What is this software?
Pmb by Sigb
Pmb by Sigb
Pmb by Sigb
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with complete administrative control, data theft, lateral movement to other systems, and persistent backdoor installation.
Likely Case
Remote code execution leading to web server compromise, data exfiltration, and potential ransomware deployment.
If Mitigated
Limited impact with proper network segmentation, but still potential for application-level compromise.
🎯 Exploit Status
Public advisory includes technical details that could be weaponized. CVSS 9.8 indicates trivial exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 7.5.6-2, 7.4.9, 7.3.18 or later
Vendor Advisory: https://forge.sigb.net/projects/pmb/files
Restart Required: Yes
Instructions:
1. Download latest patched version from PMB forge. 2. Backup current installation and database. 3. Replace files with patched version. 4. Restart web server and PMB services.
🔧 Temporary Workarounds
Network Access Restriction
linuxRestrict access to PMB application to trusted IP addresses only
iptables -A INPUT -p tcp --dport 80 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
Web Application Firewall
allDeploy WAF with deserialization attack detection rules
🧯 If You Can't Patch
- Isolate PMB system in separate network segment with strict egress filtering
- Implement application-level monitoring for suspicious deserialization patterns
🔍 How to Verify
Check if Vulnerable:
Check PMB version in administration interface or by examining version files in installation directoryCheck Version:
grep -r 'version' /path/to/pmb/installation/*.php | grep -i '7\.'Verify Fix Applied:
Verify version number is 7.5.6-2, 7.4.9, 7.3.18 or later in PMB admin interface📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to PMB endpoints
- Base64 encoded or serialized data in request logs
- Unexpected process execution from web server user
Network Indicators:
- HTTP requests containing serialized PHP objects
- Outbound connections from PMB server to unknown destinations
SIEM Query:
source="pmb_access.log" AND (method="POST" AND uri="/pmb/opac_css/*" AND size>10000)