CVE-2016-9751 in Piwigo
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in the search results front end in Piwigo 2.8.3 allows remote attackers to inject arbitrary web script or HTML via the search parameter.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 10/04/2022
The vulnerability identified as CVE-2016-9751 represents a critical cross-site scripting flaw within the Piwigo photo gallery software version 2.8.3. This issue affects the front-end search functionality where user input is not properly sanitized before being rendered back to the browser. The vulnerability stems from inadequate input validation and output encoding mechanisms that fail to neutralize malicious script content injected through the search parameter. Attackers can exploit this weakness by crafting specially formatted search queries containing malicious javascript code or html tags that execute in the context of other users' browsers when they view search results.
This vulnerability falls under the CWE-79 category of Cross-Site Scripting, specifically representing a reflected XSS attack vector where the malicious payload is reflected off the web server back to the user agent. The attack occurs when the application incorporates untrusted data into web pages without proper validation or encoding, allowing an attacker to inject client-side scripts that can execute in the victim's browser context. The impact extends beyond simple script execution as it can enable session hijacking, credential theft, and redirection to malicious websites. The vulnerability affects all users who view search results, making it particularly dangerous in environments where multiple users interact with the same gallery system.
The operational impact of this vulnerability is significant as it can be exploited remotely without requiring any authentication or privileged access to the system. An attacker can craft malicious search queries that, when viewed by other users, will execute arbitrary code in their browsers. This could lead to unauthorized access to user accounts, data exfiltration, or the deployment of malware through browser-based attacks. The vulnerability is particularly concerning in shared hosting environments or corporate settings where users may have varying levels of access and security awareness. The reflected nature of the attack means that victims only need to view the search results page containing the malicious payload, making it an easy target for social engineering attacks.
Mitigation strategies should focus on implementing proper input validation and output encoding mechanisms throughout the application. The most effective approach involves sanitizing all user-supplied input before processing or displaying it in the search results interface. This includes implementing strict content type validation, removing or encoding potentially dangerous characters, and utilizing context-appropriate encoding for html, javascript, and url contexts. Organizations should also consider implementing a Content Security Policy (CSP) header to add an additional layer of protection against script injection attacks. Regular security updates and patches should be applied immediately upon release, as this vulnerability was addressed in subsequent versions of Piwigo. Additionally, implementing web application firewalls and monitoring for suspicious search patterns can help detect and prevent exploitation attempts. The vulnerability demonstrates the critical importance of input validation in web applications and aligns with ATT&CK technique T1213 for credential access through web-based attacks.