CVE-2025-0556
📋 TL;DR
This vulnerability allows local network attackers to intercept unencrypted communication between Telerik Report Server components, potentially exposing non-sensitive information. It affects Telerik Report Server versions before 2025 Q1 (11.0.25.211) when using the older .NET Framework implementation. Organizations running vulnerable versions on local networks are at risk.
💻 Affected Systems
- Progress Telerik Report Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers on the local network could intercept and analyze all communication between service agent and app host processes, potentially discovering sensitive information despite the vendor's claim of 'non-sensitive' data transmission.
Likely Case
Local network eavesdropping could reveal internal system information, configuration details, or operational data that could be used for further attacks.
If Mitigated
With proper network segmentation and access controls, the risk is limited to authorized internal users only.
🎯 Exploit Status
Exploitation requires local network access and ability to sniff traffic between the two processes. No authentication bypass is needed as this is a network-level vulnerability.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2025 Q1 (11.0.25.211) or later
Vendor Advisory: https://docs.telerik.com/report-server/knowledge-base/kb-security-cleartext-transmission-cve-2025-0556
Restart Required: No
Instructions:
1. Download Telerik Report Server 2025 Q1 (11.0.25.211) or later from the official Telerik website. 2. Backup your current installation and configuration. 3. Run the installer and follow the upgrade process. 4. Verify the installation completes successfully.
🔧 Temporary Workarounds
Network Segmentation
allIsolate the Telerik Report Server components on a dedicated VLAN or network segment to limit exposure to potential sniffing attacks.
Host-based Firewall Rules
windowsConfigure Windows Firewall to restrict communication between the service agent and app host processes to only necessary hosts.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate the Report Server components from untrusted networks
- Deploy network monitoring and intrusion detection systems to detect sniffing attempts on the affected traffic
🔍 How to Verify
Check if Vulnerable:
Check the Telerik Report Server version in the administration interface or by examining the installation directory. Versions below 11.0.25.211 are vulnerable if using .NET Framework.Check Version:
Check the version in Telerik Report Server web interface under Administration > About, or examine the file properties of Telerik.ReportServer.exeVerify Fix Applied:
After upgrading, verify the version shows 11.0.25.211 or higher in the administration interface and confirm the application is running.📡 Detection & Monitoring
Log Indicators:
- Unusual network traffic patterns between Report Server processes
- Multiple failed connection attempts to the inter-process communication channel
Network Indicators:
- Unencrypted traffic between ports used by Telerik Report Server components
- Network sniffing tools detected on the same subnet
SIEM Query:
source="network_traffic" AND (dest_port=XXXX OR src_port=XXXX) AND protocol="TCP" AND (payload_contains="Telerik" OR application="Telerik Report Server")