CVE-2023-25613
📋 TL;DR
An LDAP injection vulnerability in Apache Kerby's LdapIdentityBackend allows attackers to manipulate LDAP queries through user-controlled input. This could enable authentication bypass, unauthorized data access, or LDAP server compromise. Organizations using Apache Kerby for authentication or identity services are affected.
💻 Affected Systems
- Apache Kerby
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete authentication bypass allowing unauthorized access to protected systems, LDAP server compromise leading to domain takeover, or sensitive data exfiltration from directory services.
Likely Case
Authentication bypass enabling unauthorized access to applications using Kerby for authentication, potentially leading to privilege escalation.
If Mitigated
Limited impact with proper input validation and LDAP query sanitization in place, though risk remains if vulnerable version is exposed.
🎯 Exploit Status
LDAP injection typically requires some user input interaction but is well-understood attack vector. No public exploits confirmed as of analysis.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.0.3
Vendor Advisory: https://lists.apache.org/thread/ynz3hhbbq6d980fzpncwbh5jd8mkyt5y
Restart Required: Yes
Instructions:
1. Download Apache Kerby 2.0.3 or later from Apache website. 2. Stop all Kerby services. 3. Replace existing Kerby installation with patched version. 4. Restart Kerby services. 5. Verify functionality.
🔧 Temporary Workarounds
Input Validation Filter
allImplement strict input validation for all user-supplied parameters used in LDAP queries
LDAP Query Sanitization
allUse parameterized LDAP queries or escape special LDAP characters in user input
🧯 If You Can't Patch
- Implement network segmentation to isolate Kerby servers from untrusted networks
- Deploy web application firewall with LDAP injection detection rules
🔍 How to Verify
Check if Vulnerable:
Check Kerby version: grep 'kerby' in application dependencies or run 'java -jar kerby-*.jar --version'Check Version:
java -jar kerby-*.jar --version 2>&1 | grep -i versionVerify Fix Applied:
Confirm version is 2.0.3 or higher and test authentication with malformed input containing LDAP special characters📡 Detection & Monitoring
Log Indicators:
- Unusual LDAP query patterns
- Authentication attempts with special characters
- Failed LDAP bind operations with malformed queries
Network Indicators:
- LDAP traffic containing injection patterns like *, (, ), \, =, or | in unexpected places
SIEM Query:
source="kerby.log" AND ("LDAP" OR "bind") AND ("*" OR "(" OR ")" OR "\\" OR "=" OR "|")