CVE-2026-2560 Overview
A command injection vulnerability has been identified in kalcaddle kodbox versions up to 1.64.05. The vulnerability exists in the run function within the file plugins/fileThumb/lib/VideoResize.class.php, which is part of the Media File Preview Plugin component. Attackers can exploit this flaw by manipulating the localFile argument to inject and execute arbitrary operating system commands on the underlying server.
Critical Impact
Remote attackers with low privileges can execute arbitrary OS commands on the server hosting kodbox, potentially leading to complete system compromise, data theft, or lateral movement within the network.
Affected Products
- kalcaddle kodbox up to version 1.64.05
- kodbox Media File Preview Plugin (plugins/fileThumb/lib/VideoResize.class.php)
Discovery Timeline
- 2026-02-16 - CVE-2026-2560 published to NVD
- 2026-02-18 - Last updated in NVD database
Technical Details for CVE-2026-2560
Vulnerability Analysis
This vulnerability is classified as OS Command Injection (CWE-77), occurring when user-controlled input is passed to system command execution functions without proper sanitization. The vulnerable component processes media files for thumbnail generation or video resizing operations, and the localFile parameter is incorporated into shell commands without adequate input validation.
The attack surface is accessible over the network by authenticated users with low privileges. When a malicious file path or specially crafted filename is processed by the VideoResize.class.php component, the attacker-controlled content is interpreted as part of an OS command, enabling arbitrary command execution on the server.
The exploit has been publicly disclosed, increasing the risk of exploitation in the wild. The vendor (kalcaddle) was contacted about this vulnerability but did not respond.
Root Cause
The root cause is improper neutralization of special elements used in an OS command. The run function in VideoResize.class.php constructs shell commands using the localFile argument without proper escaping or validation of shell metacharacters. This allows attackers to break out of the intended command context and inject additional commands using shell operators such as semicolons (;), pipes (|), or command substitution ($()).
Attack Vector
The attack is network-based and can be executed remotely. An authenticated attacker with low-level privileges can exploit this vulnerability by:
- Uploading or referencing a media file with a maliciously crafted filename
- Triggering the Media File Preview Plugin to process the file
- The vulnerable run function executes the injected commands with the privileges of the web server process
The vulnerability requires no user interaction beyond the attacker's own actions. Technical details and proof-of-concept information are available in the GitHub Gist PoC Example.
Detection Methods for CVE-2026-2560
Indicators of Compromise
- Unusual process spawning from the web server process (e.g., PHP spawning shell commands like /bin/sh, cmd.exe, or utilities like wget, curl, nc)
- Unexpected network connections originating from the kodbox server
- Anomalous entries in web server access logs referencing the VideoResize.class.php endpoint with suspicious file parameters
- Modified files or new files appearing outside normal application directories
Detection Strategies
- Monitor web application logs for requests to plugins/fileThumb/lib/VideoResize.class.php containing shell metacharacters (;, |, &, $(), backticks)
- Implement file integrity monitoring on the kodbox installation directory to detect unauthorized modifications
- Deploy web application firewall (WAF) rules to detect and block command injection patterns in file-related parameters
Monitoring Recommendations
- Enable detailed logging for the Media File Preview Plugin and monitor for processing errors or unexpected behavior
- Configure SIEM alerts for process execution chains where the web server parent process spawns command shells
- Monitor outbound network traffic from the kodbox server for unusual destinations or protocols
How to Mitigate CVE-2026-2560
Immediate Actions Required
- Disable the Media File Preview Plugin (fileThumb) if video preview functionality is not essential for operations
- Restrict access to the kodbox application to trusted users and networks only
- Implement web application firewall rules to filter command injection payloads
- Review and audit all files processed by the affected component for signs of exploitation
Patch Information
No official patch is currently available from the vendor. The vendor (kalcaddle) was contacted about this vulnerability but did not respond. Organizations should monitor the official kodbox repository for security updates and consider alternative mitigations until a fix is released.
For additional technical details, refer to the VulDB entry #346167 and the GitHub Gist Code Snippet.
Workarounds
- Remove or rename the VideoResize.class.php file to completely disable the vulnerable functionality
- Implement input validation at the application level to sanitize the localFile parameter before it reaches the vulnerable function
- Apply the principle of least privilege to the web server process to limit the impact of successful exploitation
- Deploy network segmentation to isolate the kodbox server from critical infrastructure
# Disable the vulnerable plugin by removing or renaming the affected file
mv /path/to/kodbox/plugins/fileThumb/lib/VideoResize.class.php /path/to/kodbox/plugins/fileThumb/lib/VideoResize.class.php.disabled
# Alternatively, restrict permissions to prevent execution
chmod 000 /path/to/kodbox/plugins/fileThumb/lib/VideoResize.class.php
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
