Overview
CVE-2025-13626 describes a reflected Cross-Site Scripting (XSS) vulnerability found in the myLCO WordPress plugin. This vulnerability affects all versions up to and including 0.8.1. It stems from insufficient input sanitization and output escaping of the $_SERVER['PHP_SELF'] parameter. This allows unauthenticated attackers to inject arbitrary web scripts into vulnerable pages.
Technical Details
The vulnerability exists because the myLCO plugin does not properly sanitize the $_SERVER['PHP_SELF'] parameter before using it in output. This parameter contains the current script’s filename, and an attacker can manipulate it by crafting a malicious URL that injects JavaScript code. When a user visits the crafted URL, the injected script executes in their browser, potentially allowing the attacker to steal cookies, redirect the user to a malicious site, or perform other malicious actions on behalf of the user.
The vulnerable code is located within the plugin’s files. Examining the source code reveals a lack of adequate escaping or sanitization mechanisms. Specifically, the vulnerability manifests where the plugin utilizes the $_SERVER['PHP_SELF'] variable directly in the HTML output without proper escaping.
CVSS Analysis
The Common Vulnerability Scoring System (CVSS) assigns CVE-2025-13626 a score of 6.1 (Medium). This score reflects the following characteristics:
- Attack Vector (AV): Network (N)
- Attack Complexity (AC): Low (L)
- Privileges Required (PR): None (N)
- User Interaction (UI): Required (R)
- Scope (S): Changed (C)
- Confidentiality Impact (C): Low (L)
- Integrity Impact (I): Low (L)
- Availability Impact (A): None (N)
The “User Interaction Required” component is crucial. The attacker needs to trick a user into clicking a specially crafted link for the XSS attack to succeed.
Possible Impact
Successful exploitation of this vulnerability could have several negative consequences:
- Account Takeover: An attacker could potentially steal a logged-in user’s session cookie and use it to impersonate them.
- Malicious Redirection: Users could be redirected to phishing websites or other malicious destinations.
- Website Defacement: An attacker could modify the content of the affected page.
- Credential Harvesting: JavaScript code injected by the attacker could be used to steal user credentials.
Mitigation or Patch Steps
The most effective mitigation is to update the myLCO plugin to a version that addresses this vulnerability. Check the WordPress plugin repository for an updated version or consider disabling the plugin entirely if an update is not available.
If updating is not immediately possible, consider implementing a Web Application Firewall (WAF) rule to filter requests containing potentially malicious payloads targeting the $_SERVER['PHP_SELF'] parameter. However, this should be considered a temporary workaround and not a replacement for patching the vulnerability.