CVE-2026-48941 in K2 Extension
Summary
by MITRE • 06/25/2026
The K2 frontend `item.checkin` task accepts an unauthenticated `sigProFolder` query parameter and uses it directly to address a `JFolder::delete()` call under `/media/k2/galleries/`
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Analysis
by VulDB Data Team • 06/25/2026
This vulnerability exists within the K2 frontend component where the item.checkin task processes an unauthenticated sigProFolder query parameter without proper validation or sanitization. The flaw allows attackers to manipulate this parameter directly into a JFolder::delete() function call, which operates within the /media/k2/galleries/ directory path. This represents a critical authorization bypass vulnerability that enables arbitrary file deletion operations on the web server filesystem.
The technical implementation exposes a classic path traversal and privilege escalation vector where the sigProFolder parameter is not properly validated against authorized directories or user permissions. When the parameter is passed directly to JFolder::delete(), it creates a dangerous condition where any attacker can specify arbitrary directory paths within the galleries folder structure, potentially leading to complete compromise of the media storage system. This vulnerability operates under CWE-22 Path Traversal and CWE-798 Hardcoded Credentials or Security Misconfiguration principles.
The operational impact of this vulnerability extends beyond simple file deletion to include potential data exfiltration, service disruption, and further attack escalation opportunities. Attackers could leverage this to remove critical gallery files, delete user-generated content, or potentially disrupt the entire K2 media management functionality. The unauthenticated nature means no prior access is required to exploit this flaw, making it particularly dangerous in production environments where K2 is deployed.
Mitigation strategies should include immediate parameter validation that restricts sigProFolder values to predefined authorized folders and implements strict path sanitization routines before any filesystem operations occur. The system must enforce proper authentication checks for all media management functions and implement input filtering that prevents directory traversal sequences. Security measures should also include limiting the permissions of the web server process running K2 to minimize potential damage from successful exploitation. Organizations should consider implementing the principle of least privilege and apply the ATT&CK technique T1059 Command and Scripting Interpreter for any further automated exploitation attempts. Regular security audits should verify that all user inputs are properly sanitized before being used in filesystem operations, preventing similar vulnerabilities from persisting in other components of the application stack.