CVE-2021-43350
📋 TL;DR
CVE-2021-43350 is an LDAP injection vulnerability in Apache Traffic Control Traffic Ops that allows unauthenticated attackers to manipulate LDAP filters through specially-crafted usernames. This can lead to authentication bypass, information disclosure, or LDAP manipulation. All Apache Traffic Control deployments with Traffic Ops exposed are affected.
💻 Affected Systems
- Apache Traffic Control Traffic Ops
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through LDAP injection leading to authentication bypass, privilege escalation, and potential remote code execution via LDAP manipulation.
Likely Case
Authentication bypass allowing unauthorized access to Traffic Ops administrative functions and potential LDAP data exfiltration.
If Mitigated
Limited impact with proper network segmentation and authentication controls, though LDAP injection could still expose sensitive directory information.
🎯 Exploit Status
Public proof-of-concept exists in security advisories. Simple HTTP request manipulation required. No authentication needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Apache Traffic Control 5.1.2 and later
Vendor Advisory: https://trafficcontrol.apache.org/security/
Restart Required: Yes
Instructions:
1. Upgrade Apache Traffic Control to version 5.1.2 or later. 2. Restart Traffic Ops service. 3. Verify LDAP filter sanitization in login endpoint.
🔧 Temporary Workarounds
Network Access Control
linuxRestrict access to Traffic Ops login endpoint using firewall rules or network segmentation.
iptables -A INPUT -p tcp --dport <traffic-ops-port> -s <trusted-networks> -j ACCEPT
iptables -A INPUT -p tcp --dport <traffic-ops-port> -j DROP
Web Application Firewall
allDeploy WAF rules to block LDAP injection patterns in username parameters.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate Traffic Ops from untrusted networks
- Deploy web application firewall with LDAP injection detection rules
🔍 How to Verify
Check if Vulnerable:
Check Apache Traffic Control version. If version < 5.1.2 and LDAP authentication is configured, system is vulnerable.Check Version:
Check Traffic Ops configuration or run: traffic_ops --versionVerify Fix Applied:
After patching, attempt LDAP injection via username parameter at POST /login endpoint. Should return sanitized error or reject malicious input.📡 Detection & Monitoring
Log Indicators:
- Unusual LDAP query patterns in Traffic Ops logs
- Failed login attempts with special characters in username field
- LDAP error messages containing user-supplied input
Network Indicators:
- HTTP POST requests to /login endpoint with special characters (*, (, ), &, |, =) in username parameter
- Unusual LDAP traffic from Traffic Ops server
SIEM Query:
source="traffic-ops.log" AND "POST /login" AND username=/(\*|\(|\)|&|\||=)/🔗 References
- http://www.openwall.com/lists/oss-security/2021/11/11/3
- http://www.openwall.com/lists/oss-security/2021/11/11/4
- http://www.openwall.com/lists/oss-security/2021/11/17/1
- https://trafficcontrol.apache.org/security/
- http://www.openwall.com/lists/oss-security/2021/11/11/3
- http://www.openwall.com/lists/oss-security/2021/11/11/4
- http://www.openwall.com/lists/oss-security/2021/11/17/1
- https://trafficcontrol.apache.org/security/
