CVE-2016-9998 in SPIP
Summary
by MITRE
SPIP 3.1.x suffer from a Reflected Cross Site Scripting Vulnerability in /ecrire/exec/info_plugin.php involving the `$plugin` parameter, as demonstrated by a /ecrire/?exec=info_plugin URL.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 10/12/2022
The vulnerability identified as CVE-2016-9998 represents a reflected cross site scripting flaw in the SPIP content management system version 3.1.x. This security weakness specifically affects the /ecrire/exec/info_plugin.php script where the `$plugin` parameter is improperly handled, creating an avenue for malicious attackers to inject arbitrary script code into web pages viewed by other users. The vulnerability manifests when users navigate to the /ecrire/?exec=info_plugin URL with a crafted plugin parameter value, allowing for the execution of malicious scripts in the context of the victim's browser session.
The technical implementation of this vulnerability stems from insufficient input validation and output sanitization within the SPIP application's administrative interface. When the system processes the `$plugin` parameter without proper encoding or filtering mechanisms, it directly incorporates user-supplied data into the HTTP response without adequate protection against script injection. This flaw aligns with CWE-79, which specifically addresses cross site scripting vulnerabilities where untrusted data is improperly integrated into web pages. The reflected nature of this vulnerability means that the malicious script code is reflected back to the user through the server's response, making it particularly dangerous as it can be delivered via email links or malicious websites that direct users to the vulnerable endpoint.
The operational impact of this vulnerability extends beyond simple script execution, potentially enabling attackers to perform session hijacking, deface the website, steal sensitive information, or redirect users to malicious sites. An attacker could craft a URL containing malicious JavaScript code within the plugin parameter that would execute when a victim accesses the administrative interface, potentially compromising the entire system if the victim has administrative privileges. This vulnerability particularly affects web applications following the ATT&CK framework's TA0001 Initial Access and TA0002 Execution tactics, as it provides an entry point for attackers to establish a foothold within the system and execute arbitrary code.
Mitigation strategies for CVE-2016-9998 should prioritize immediate patching of the SPIP 3.1.x installation to the latest available version that addresses this specific vulnerability. Organizations should implement proper input validation and output encoding mechanisms throughout the application, particularly for parameters that are directly rendered in web responses. The implementation of Content Security Policy headers can provide additional protection against script execution, while regular security audits and input sanitization practices should be enforced. Security teams should also consider implementing web application firewalls to detect and block malicious requests containing known attack patterns, and conduct regular penetration testing to identify similar vulnerabilities within the application's codebase. Organizations using older versions of SPIP should plan for immediate migration to supported releases to eliminate exposure to this and related vulnerabilities.