CVE-2026-4589 Overview
A Server-Side Request Forgery (SSRF) vulnerability has been identified in kalcaddle kodbox version 1.64. The vulnerability exists within the PathDriverUrl function located in the file /workspace/source-code/app/controller/explorer/editor.class.php, which is part of the fileGet Endpoint component. Manipulation of the path argument allows attackers to forge server-side requests to arbitrary destinations, potentially exposing internal services and sensitive data.
Critical Impact
This SSRF vulnerability enables remote attackers with low privileges to make arbitrary server-side requests, potentially accessing internal network resources, sensitive metadata services, or performing port scanning of internal infrastructure.
Affected Products
- kalcaddle kodbox version 1.64
- kodbox fileGet Endpoint component
- kodbox editor.class.php module
Discovery Timeline
- 2026-03-23 - CVE-2026-4589 published to NVD
- 2026-03-23 - Last updated in NVD database
Technical Details for CVE-2026-4589
Vulnerability Analysis
This vulnerability is classified as Server-Side Request Forgery (CWE-918), a critical web application security flaw that allows attackers to induce the server-side application to make HTTP requests to an arbitrary domain of the attacker's choosing. In the context of kodbox, the vulnerable PathDriverUrl function within the fileGet Endpoint fails to properly validate or sanitize the path parameter before using it to construct server-side requests.
The exploitation requires network access and low-level privileges, meaning authenticated users can abuse this functionality. The vulnerability can lead to confidentiality, integrity, and availability impacts as attackers may access internal services, read sensitive data from metadata endpoints, or interact with internal APIs that should not be externally accessible.
Root Cause
The root cause of this vulnerability lies in insufficient input validation within the PathDriverUrl function in /workspace/source-code/app/controller/explorer/editor.class.php. The path argument is not properly sanitized or validated against an allowlist of permitted destinations before being used to construct and execute server-side HTTP requests. This allows attackers to supply arbitrary URLs or internal IP addresses, causing the server to make requests on their behalf.
Attack Vector
The attack can be launched remotely over the network by authenticated users with low privileges. An attacker can exploit this vulnerability by manipulating the path parameter in requests to the fileGet Endpoint. This enables the attacker to:
- Probe internal network infrastructure and services not exposed to the internet
- Access cloud metadata services (e.g., AWS EC2 metadata at http://169.254.169.254/)
- Bypass firewall restrictions by using the vulnerable server as a proxy
- Potentially escalate to more severe attacks depending on internal service configurations
The vulnerability is publicly documented and exploit information is available through security research channels. The vendor was contacted about this disclosure but did not respond.
Detection Methods for CVE-2026-4589
Indicators of Compromise
- Unusual outbound HTTP/HTTPS requests from the kodbox server to internal IP ranges (e.g., 10.x.x.x, 172.16.x.x, 192.168.x.x)
- Requests to cloud metadata endpoints such as 169.254.169.254 originating from the application server
- Abnormal patterns in the path parameter within fileGet Endpoint requests containing URLs or IP addresses
- Log entries showing requests to the editor.class.php endpoint with suspicious path values
Detection Strategies
- Implement Web Application Firewall (WAF) rules to detect and block SSRF patterns in the path parameter
- Monitor application logs for requests to the fileGet Endpoint containing URL schemes (http://, https://, file://) in the path argument
- Deploy network-level monitoring to identify outbound connections from the kodbox server to unexpected internal or external destinations
- Use intrusion detection systems (IDS) to alert on traffic patterns indicative of SSRF exploitation
Monitoring Recommendations
- Enable detailed logging for all requests to the /workspace/source-code/app/controller/explorer/editor.class.php endpoint
- Configure alerts for any requests where the path parameter contains IP addresses or URL schemes
- Monitor DNS query logs from the kodbox server for unusual domain lookups
- Implement network segmentation monitoring to detect unauthorized access attempts to internal services
How to Mitigate CVE-2026-4589
Immediate Actions Required
- Restrict network access to the kodbox fileGet Endpoint to trusted users only
- Implement a Web Application Firewall (WAF) rule to block requests containing suspicious patterns in the path parameter
- Consider disabling the affected fileGet functionality if not critical to operations until a patch is available
- Isolate the kodbox server from sensitive internal network resources using network segmentation
Patch Information
No official patch is currently available from the vendor. The vendor was contacted early about this disclosure but did not respond. Organizations should monitor VulDB Entry #352425 and the official kodbox repository for any future security updates. In the absence of a vendor patch, implementing the workarounds below is strongly recommended.
Workarounds
- Implement server-side URL validation to restrict the path parameter to an allowlist of approved domains and file paths
- Block outbound requests from the kodbox server to internal IP ranges and cloud metadata endpoints using firewall rules
- Deploy a reverse proxy with request inspection capabilities to filter malicious SSRF payloads
- Consider implementing a URL validation library that prevents requests to private IP ranges, localhost, and link-local addresses
# Example firewall rules to block SSRF to internal networks (iptables)
# Block outbound to private IP ranges from kodbox server
iptables -A OUTPUT -d 10.0.0.0/8 -j DROP
iptables -A OUTPUT -d 172.16.0.0/12 -j DROP
iptables -A OUTPUT -d 192.168.0.0/16 -j DROP
iptables -A OUTPUT -d 169.254.169.254 -j DROP
iptables -A OUTPUT -d 127.0.0.0/8 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
