CVE-2025-54597: Heimdall Prior to 2.7.3 Vulnerable to Cross-Site Scripting (XSS)
Heimdall, a popular application dashboard, has a security vulnerability that could allow attackers to inject malicious scripts into user browsers. This blog post provides details on CVE-2025-54597, a Cross-Site Scripting (XSS) vulnerability affecting Heimdall versions before 2.7.3. We'll discuss the technical details, potential impact, and recommended steps to mitigate this risk.
Vulnerability Details
- CVE ID: CVE-2025-54597
- Description: LinuxServer.io Heimdall before 2.7.3 allows XSS via the q parameter. This means an attacker could inject arbitrary JavaScript code into the application, potentially stealing user credentials or performing other malicious actions on behalf of the user.
- CVSS Score: 7.2 (HIGH)
- CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
- CVSS Explanation: This vulnerability has a high severity because it's remotely exploitable (AV:N) with low complexity (AC:L) and requires no user interaction (UI:N). Although the impact to Confidentiality and Integrity is low, the Scope is changed (S:C) making it possible to inject code into the context of a different part of the application.
- Exploit Requirements: An attacker needs to craft a malicious URL containing the XSS payload within the 'q' parameter. A user needs to visit the crafted URL while logged into Heimdall, or otherwise be tricked into executing the malicious request.
- Affected Vendor: linuxserver.io
- Affected Product: Heimdall
- Affected Version: Versions prior to 2.7.3
- CWE: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-79, Cross-Site Scripting (XSS), occurs when a web application does not properly sanitize user-supplied input before displaying it in a web page. This allows attackers to inject malicious scripts that can be executed by other users' browsers.
Timeline of Events
- Reported: Unknown
- Fixed: Addressed in commit d1a96dd752ba30dc56380400dd2587d8abb8e9d1
- Patch Released: Version 2.7.3
Exploitability & Real-World Risk
The exploitability of this XSS vulnerability is relatively high due to the low attack complexity. An attacker could potentially craft a malicious link and distribute it via email, social media, or other channels. If a user clicks on the link while logged into Heimdall, the attacker's script could be executed. This could lead to session hijacking, account compromise, or defacement of the Heimdall dashboard.
Recommendations
- Upgrade to version 2.7.3 or later: This version contains the fix for the XSS vulnerability.
- Input Validation: Ensure all user inputs are properly validated and sanitized to prevent XSS attacks.
- Content Security Policy (CSP): Implement CSP to restrict the sources from which scripts can be loaded, mitigating the impact of XSS vulnerabilities.
Technical Insight
The vulnerability stems from the Heimdall application failing to properly sanitize user-provided input in the `q` parameter of a request. This allows an attacker to inject arbitrary HTML and JavaScript code, which is then rendered by the user's browser, leading to the execution of the attacker's malicious script.
Credit to Researcher(s)
The discovery and reporting of this vulnerability is unknown based on the provided information.
References
- Commit d1a96dd752ba30dc56380400dd2587d8abb8e9d1 on GitHub
- Heimdall v2.7.2...v2.7.3 Comparison
- CVE-2025-54597
Tags
#Heimdall #XSS #CVE-2025-54597 #linuxserver.io #security #vulnerability #cross-site scripting
Summary: Heimdall versions before 2.7.3 are vulnerable to Cross-Site Scripting (XSS) via the 'q' parameter. An attacker could inject arbitrary JavaScript code into the application, potentially stealing user credentials or performing other malicious actions.
CVE ID: CVE-2025-54597
Risk Analysis: Successful exploitation of this XSS vulnerability could allow an attacker to steal user credentials, deface the Heimdall dashboard, or perform other malicious actions on behalf of the user. This can damage the reputation of the affected organization and compromise sensitive data.
Recommendation: Upgrade to Heimdall version 2.7.3 or later to patch the XSS vulnerability. Implement robust input validation and sanitization measures to prevent future XSS attacks.
Timeline
- 2025-07-27: CVE-2025-54597 assigned and published.