CVE-2025-11242: Okulistik SSRF Vulnerability

CVE-2025-11242 Overview

CVE-2025-11242 is a Server-Side Request Forgery (SSRF) vulnerability affecting Teknolist Computer Systems Software Publishing Industry and Trade Inc. Okulistik software through version 21102025. This vulnerability allows attackers to manipulate server-side requests, potentially enabling unauthorized access to internal resources, data exfiltration, and further exploitation of backend systems.

Critical Impact

This SSRF vulnerability can allow attackers to bypass network security controls, access internal services, and potentially pivot to other systems within the network infrastructure.

Affected Products

• Teknolist Okulistik through version 21102025

Discovery Timeline

• 2026-02-10 - CVE-2025-11242 published to NVD
• 2026-02-10 - Last updated in NVD database

Technical Details for CVE-2025-11242

Vulnerability Analysis

This Server-Side Request Forgery (SSRF) vulnerability in Okulistik allows attackers to craft malicious requests that the server will execute on their behalf. SSRF vulnerabilities occur when an application fetches a remote resource without properly validating the user-supplied URL, allowing attackers to coerce the application into sending requests to unintended destinations.

The vulnerability is classified under CWE-918 (Server-Side Request Forgery), which describes a weakness where the web server receives a URL or similar request from an upstream component and retrieves the contents of this URL without sufficiently ensuring that the request is being sent to the expected destination.

In the context of Okulistik, attackers can exploit this vulnerability remotely over the network without requiring any authentication or user interaction. Successful exploitation could lead to unauthorized access to sensitive internal resources, potential data leakage, and the ability to perform actions on behalf of the vulnerable server.

Root Cause

The root cause of this vulnerability is improper validation of user-supplied URLs or request parameters within the Okulistik application. When the application processes external resource requests, it fails to adequately verify that the destination is legitimate and safe, allowing attackers to redirect these requests to arbitrary internal or external endpoints.

Attack Vector

The attack vector for CVE-2025-11242 is network-based, meaning attackers can exploit this vulnerability remotely without physical access to the target system. The exploitation process typically involves:

1. Identifying input fields or API endpoints that accept URLs or network resource identifiers
2. Crafting malicious requests containing internal IP addresses, localhost references, or cloud metadata endpoints
3. Submitting these requests to the vulnerable Okulistik application
4. The server processes the request and fetches the attacker-specified resource
5. The attacker receives the response data or uses the request to interact with internal services

Common SSRF attack targets include internal network services, cloud provider metadata endpoints (such as 169.254.169.254), and administrative interfaces that are typically protected by network segmentation.

Detection Methods for CVE-2025-11242

Indicators of Compromise

• Unusual outbound requests from the Okulistik server to internal IP ranges (e.g., 10.x.x.x, 172.16.x.x, 192.168.x.x)
• Requests targeting cloud metadata endpoints such as 169.254.169.254 or metadata.google.internal
• Server logs showing requests to localhost or loopback addresses (127.0.0.1, ::1)
• Unexpected DNS lookups for internal hostnames originating from the web application server

Detection Strategies

• Implement web application firewall (WAF) rules to detect and block SSRF attack patterns in URL parameters
• Monitor server-side outbound network traffic for connections to RFC 1918 private IP addresses
• Deploy network intrusion detection systems (IDS) to identify anomalous request patterns from the Okulistik server
• Review application logs for URL parameters containing internal network references or encoded IP addresses

Monitoring Recommendations

• Enable detailed logging for all outbound HTTP requests made by the Okulistik application
• Configure alerts for any server-initiated connections to internal network segments or cloud metadata services
• Implement network segmentation monitoring to detect lateral movement attempts originating from the web server
• Regularly audit application logs for suspicious URL patterns including IP address encodings (decimal, hexadecimal, octal)

How to Mitigate CVE-2025-11242

Immediate Actions Required

• Restrict network egress from the Okulistik server to only necessary external destinations using firewall rules
• Implement URL allowlisting for any functionality that requires fetching external resources
• Block access to cloud provider metadata endpoints from the application server
• Review and audit all user input handling related to URL processing in the application

Patch Information

Refer to the USOM Security Advisory TR-26-0048 for official vendor guidance and patch information. Organizations running Okulistik should contact Teknolist Computer Systems for the latest security updates addressing this vulnerability.

Workarounds

• Deploy a web application firewall (WAF) with SSRF protection rules to filter malicious requests
• Implement strict egress filtering on the network level to prevent the server from accessing internal resources
• Disable or restrict any application features that allow fetching external URLs until a patch is available
• Use network segmentation to isolate the Okulistik server from sensitive internal systems and services