CVE-2025-26846
📋 TL;DR
A missing authorization vulnerability in Znuny's Generic Interface allows attackers to modify ticket metadata without proper permission checks. This affects all Znuny installations before version 7.1.4 that have the Generic Interface enabled. Attackers can exploit this to escalate privileges and manipulate ticket data.
💻 Affected Systems
- Znuny (formerly OTRS)
📦 What is this software?
Znuny by Znuny
Znuny by Znuny
Znuny by Znuny
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through privilege escalation leading to data theft, ticket manipulation, and potential lateral movement within the ticketing system.
Likely Case
Unauthorized modification of ticket metadata, including priority changes, status updates, and assignment modifications, potentially disrupting business processes.
If Mitigated
Limited impact with proper network segmentation and access controls, though the vulnerability still exists at the application layer.
🎯 Exploit Status
Exploitation requires access to the Generic Interface endpoint. The vulnerability is in the permission validation logic, making exploitation straightforward once access is obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 7.1.4
Vendor Advisory: https://www.znuny.org/en/advisories/zsa-2025-02
Restart Required: Yes
Instructions:
1. Backup your Znuny installation and database. 2. Download Znuny 7.1.4 from the official website. 3. Follow the upgrade instructions in the Znuny documentation. 4. Restart the Znuny service after upgrade completion.
🔧 Temporary Workarounds
Disable Generic Interface
allTemporarily disable the Generic Interface to prevent exploitation while planning the upgrade.
Edit Znuny configuration to disable Generic Interface modules
Network Access Restriction
linuxRestrict network access to the Generic Interface endpoints using firewall rules.
iptables -A INPUT -p tcp --dport [znuny-port] -s [trusted-ips] -j ACCEPT
iptables -A INPUT -p tcp --dport [znuny-port] -j DROP
🧯 If You Can't Patch
- Implement strict network segmentation to isolate Znuny systems from untrusted networks
- Enable detailed logging and monitoring of Generic Interface access and ticket modification activities
🔍 How to Verify
Check if Vulnerable:
Check Znuny version via admin interface or by examining the installed package version. If version is below 7.1.4 and Generic Interface is enabled, the system is vulnerable.Check Version:
Check Znuny admin interface or run: grep -i version /opt/znuny/Kernel/Config.pm (adjust path as needed)Verify Fix Applied:
After upgrading to 7.1.4, verify the version in the admin interface and test that permission checks are properly enforced when using Generic Interface operations.📡 Detection & Monitoring
Log Indicators:
- Unusual Generic Interface access patterns
- Ticket metadata modifications from unexpected users or IPs
- Failed permission checks in application logs
Network Indicators:
- Unusual traffic to Generic Interface endpoints
- Multiple ticket update requests from single source
SIEM Query:
source="znuny.logs" AND ("GenericInterface" OR "ticket update") AND NOT user IN [authorized_users]