Authenticated SSRF in Koillection Scraper Subsystem

Executive Summary

CVE-2026-50888 is a vulnerability in Koillection version 1.8.0 where an authenticated user can exploit a custom scraper subsystem to perform Server-Side Request Forgery (SSRF) attacks.

This happens because the system allows users to submit arbitrary URLs and define extraction rules that the server fetches and processes without proper input validation.

As a result, attackers can craft URLs that make the server send requests to internal HTTP services and retrieve sensitive response content.

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Impact Analysis

The vulnerability allows authenticated users, even with low privileges, to scan internal resources that are normally inaccessible from outside.

Attackers can trigger outbound requests to internal addresses and extract sensitive data by using XPath or path extraction rules.

This can lead to unauthorized disclosure of internal service responses, potentially exposing sensitive information within the internal network.

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Detection Guidance

Detection of CVE-2026-50888 involves monitoring for unusual outbound HTTP requests originating from authenticated users, especially those targeting internal network addresses.

Since the vulnerability allows authenticated users to submit arbitrary URLs to the custom scraper subsystem, you can look for logs or network traffic showing requests to internal services triggered by user actions.

Suggested commands include inspecting web server or application logs for suspicious URL parameters or payloads that contain internal IP addresses or unusual URL patterns.

• Use network monitoring tools (e.g., tcpdump or Wireshark) to capture outbound HTTP requests from the server and filter for internal IP ranges.
• Example tcpdump command: tcpdump -i <interface> 'dst net 10.0.0.0/8 or dst net 192.168.0.0/16 or dst net 172.16.0.0/12' and port 80 or port 443
• Search application logs for URL parameters containing internal IP addresses or suspicious URL patterns submitted by authenticated users.

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Mitigation Strategies

Immediate mitigation steps include disabling or restricting the custom scraper subsystem feature, especially for low-privileged or regular authenticated users.

Implement strict input validation and sanitization on URLs submitted to the scraper subsystem to prevent requests to internal network addresses.

Limit the ability of users to define extraction rules that could be used to disclose sensitive response content.

Monitor and restrict outbound HTTP requests from the server to internal network addresses using firewall rules or network segmentation.

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Compliance Impact

CVE-2026-50888 allows authenticated users to perform SSRF attacks that can probe internal services and retrieve sensitive response content. This exposure of internal data could lead to unauthorized access to sensitive information.

Such unauthorized access and potential data disclosure may impact compliance with standards and regulations like GDPR and HIPAA, which require protection of personal and sensitive data from unauthorized access and breaches.

Therefore, exploitation of this vulnerability could result in violations of data protection requirements mandated by these regulations.

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