CVE-2025-59524 in horilla
Summary
by MITRE • 09/24/2025
Horilla is a free and open source Human Resource Management System (HRMS). Prior to version 1.4.0, the file upload flow performs validation only in the browser and does not enforce server-side checks. An attacker can bypass the client-side validation (for example, with an intercepting proxy or by submitting a crafted request) to store an executable HTML document on the server. When an administrator or other privileged user views the uploaded file, the embedded script runs in their context and sends session cookies (or other credentials) to an attacker-controlled endpoint. The attacker then reuses those credentials to impersonate the admin. This issue has been patched in version 1.4.0.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 09/30/2025
The vulnerability identified as CVE-2025-59524 affects Horilla, a free and open source Human Resource Management System that serves as a comprehensive platform for organizational personnel management. This security flaw represents a critical server-side validation bypass that undermines the fundamental security controls designed to protect the system from malicious file uploads. The vulnerability specifically exists in versions prior to 1.4.0 where the application's file upload functionality relies entirely on client-side validation mechanisms without implementing corresponding server-side checks, creating a significant attack surface that can be exploited by threat actors.
The technical implementation of this vulnerability stems from the application's failure to enforce mandatory server-side validation of uploaded files. The system performs validation exclusively within the browser environment, allowing attackers to bypass these security controls through various means including intercepting proxies or direct request manipulation. When an attacker successfully bypasses the client-side validation, they can upload executable HTML documents containing malicious scripts to the server. This flaw directly maps to CWE-434, which describes the weakness of allowing files to be uploaded or saved to a privileged directory without proper validation, and also aligns with CWE-502, addressing the insecure deserialization of untrusted data that can occur when processing uploaded content.
The operational impact of this vulnerability is severe and potentially devastating for organizations relying on the Horilla system. An attacker who successfully exploits this vulnerability can gain elevated privileges by targeting administrators or other privileged users who view the maliciously uploaded files. The malicious HTML documents contain embedded scripts that execute in the context of the victim user's browser session, enabling the attacker to extract session cookies and other sensitive credentials. This credential theft mechanism allows for full administrative compromise of the system, enabling attackers to perform unauthorized actions including modifying employee records, accessing confidential personnel data, altering system configurations, and potentially establishing persistent access through the stolen administrative credentials. The attack vector is particularly dangerous because it leverages the trust relationship between the application and its administrators, making detection more difficult.
The security implications extend beyond simple credential theft to encompass a complete compromise of the system's integrity and confidentiality. This vulnerability enables privilege escalation attacks that can result in unauthorized data access, modification, and deletion. The attack chain follows typical patterns associated with the attack technique T1078.004 in the MITRE ATT&CK framework, which covers legitimate credentials used for persistence and privilege escalation. Organizations using vulnerable versions of Horilla should immediately implement the patch released in version 1.4.0, which enforces mandatory server-side validation of uploaded files. Additional mitigations include implementing proper file type restrictions, conducting regular security audits of upload functionality, and deploying web application firewalls to detect and prevent malicious file upload attempts. The vulnerability demonstrates the critical importance of defense-in-depth principles where client-side validation should never be the sole line of defense against malicious file uploads, and server-side validation must always be implemented as a mandatory security control.