CVE-2025-31131: Path Traversal Vulnerability in YesWiki System

Overview

In this article, we will be discussing the recently discovered “CVE-2025-31131” vulnerability. The software affected is YesWiki, a wiki creation system written in PHP. This vulnerability poses a significant threat to system security and data integrity, as it allows attackers to read arbitrary files on the server. Given the degree of potential system compromise or data leakage, it is crucial for administrators and users to understand the nature of this vulnerability, its potential impact, and the steps needed for mitigation.

Vulnerability Summary

CVE ID: CVE-2025-31131
Severity: High (CVSS Score: 8.6)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

YesWiki | Versions Prior to 4.5.2

How the Exploit Works

The vulnerability lies in the ‘squelette’ parameter of YesWiki’s system. This parameter is not properly sanitized, making it susceptible to path traversal attacks. In this type of attack, an attacker manipulates variables referencing files with ‘..’ sequences and its variations. By doing this, the attacker can access directories and files that they should not be able to access. This can lead to the reading of sensitive data or even system compromise if system files or services are affected.

Conceptual Example Code

Here is a conceptual example of how this vulnerability might be exploited. This is a sample HTTP request that uses the squelette parameter to attempt a path traversal attack.

GET /index.php?wiki=squelette&param=../../../etc/passwd HTTP/1.1
Host: target.example.com

In this example, the attacker attempts to read the ‘/etc/passwd’ file, a standard Unix file that contains basic user account information. If the attack is successful, the server would return the contents of this file, potentially revealing sensitive information.

Mitigation

The primary mitigation for this vulnerability is to apply the vendor’s patch. YesWiki has already addressed this issue in version 4.5.2, so upgrading to this version or later will resolve the vulnerability. If patching is not immediately possible, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can provide temporary mitigation. These systems can be configured to block path traversal attempts, helping to protect the system until the patch can be applied.