CVE-2025-27092
Remediation/Mitigation Strategy for CVE-2025-27092 in GHOSTS Framework
This document outlines the remediation strategy for CVE-2025-27092, a path traversal vulnerability discovered in the GHOSTS user simulation framework.
1. Vulnerability Description:
- Vulnerability: Path Traversal
- Affected Software: GHOSTS Framework
- Affected Version: 8.0.0.0
- Endpoint Affected:
/api/npcs/{id}/photo
- Description: The
/api/npcs/{id}/photo
endpoint, intended for serving NPC profile photos, is susceptible to path traversal. When an NPC is created with a craftedphotoLink
containing directory traversal sequences (e.g.,../
,..\
), the application processes these sequences without proper validation or sanitization. This allows an attacker to read arbitrary files from the server’s filesystem, potentially exposing sensitive information.
2. Severity:
- CVSS v3 Score: 8.7 (High)
- Vector String: Based on the CVSS data provided (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N)
- Explanation: The vulnerability is rated as High severity because it allows an authenticated attacker (low privileges required) to remotely read sensitive files on the server without user interaction, potentially compromising the confidentiality of the system. The impact is limited to information disclosure, but the scope is unchanged, meaning the vulnerable component remains the only affected element.
3. Known Exploit:
- The report indicates that an attacker can exploit this vulnerability by creating an NPC with a malicious
photoLink
value that contains path traversal sequences (e.g.,../
,..\
). When the application attempts to retrieve the “photo” using the crafted link, it will traverse outside of the intended photo directory and access arbitrary files on the server. - Example Exploit Scenario: An attacker creates an NPC with
photoLink
set to../../../../etc/passwd
. When the application tries to serve the photo for that NPC, it will instead serve the contents of the/etc/passwd
file.
4. Remediation Strategy:
The primary remediation strategy is to upgrade to the patched version of the GHOSTS framework.
- Action: Upgrade GHOSTS to version 8.2.7.90 or later immediately.
- Rationale: Version 8.2.7.90 addresses the path traversal vulnerability by implementing proper input validation and sanitization on the
photoLink
parameter. This is the recommended and most effective solution.
5. Mitigation Strategies (Until Upgrade is Possible):
If an immediate upgrade is not possible, implement the following mitigation strategies:
- Input Validation and Sanitization (Temporary Patch - Not Recommended as a Long-Term Solution):
- Implement Input Validation: Modify the
/api/npcs/{id}/photo
endpoint code to rigorously validate and sanitize thephotoLink
parameter. - Sanitize the photoLink: Remove all path traversal sequences (e.g.,
../
,..\
,./
,.\
) from thephotoLink
before attempting to access the file. - Whitelist Approach: Consider using a whitelist of allowed photo directories or file extensions to further restrict access. This is generally more secure than a blacklist approach.
- Implement Input Validation: Modify the
- Access Control Restrictions:
- Least Privilege Principle: Ensure that the web application process is running with the minimum necessary privileges. Restrict its access to only the directories and files required for its operation.
- File System Permissions: Review and tighten file system permissions to prevent the web application process from accessing sensitive files.
- Web Application Firewall (WAF) Rules:
- Configure a WAF to detect and block requests containing path traversal sequences in the
photoLink
parameter. This can provide an additional layer of defense.
- Configure a WAF to detect and block requests containing path traversal sequences in the
6. Verification:
After applying the remediation or mitigation strategies, verify their effectiveness:
- Upgrade Verification: After upgrading to version 8.2.7.90 or later, verify that the
/api/npcs/{id}/photo
endpoint no longer allows path traversal. Attempt to exploit the vulnerability with the same techniques used previously. - Mitigation Verification: If mitigation strategies were implemented, thoroughly test the input validation and sanitization logic to ensure that it effectively prevents path traversal attacks. Verify that the WAF is blocking malicious requests.
7. Monitoring:
- Implement monitoring and logging to detect any attempts to exploit the path traversal vulnerability.
- Review logs regularly for suspicious activity related to the
/api/npcs/{id}/photo
endpoint.
8. Long-Term Considerations:
- Establish a secure development lifecycle (SDLC) that includes regular security code reviews and penetration testing to identify and address vulnerabilities early in the development process.
- Stay informed about security advisories and updates for the GHOSTS framework and other software components.
- Consider implementing a vulnerability management program to proactively identify and remediate vulnerabilities in your environment.
Important Notes:
- The mitigation strategies provided are temporary measures and should not be considered a substitute for upgrading to the patched version of the GHOSTS framework.
- Implementing input validation and sanitization can be complex and error-prone. It is important to thoroughly test the code to ensure that it effectively prevents path traversal attacks.
- It’s crucial to apply these recommendations promptly to protect your system from potential attacks.
Assigner
- GitHub, Inc. [email protected]
Date
- Published Date: 2025-02-19 22:16:56
- Updated Date: 2025-02-27 20:18:13