CVE-2013-6111 in Mod Pagespeed
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in the mod_pagespeed module 0.x, 1.0.22.7, 1.1.x, 1.24.1, 1.3.25.1 through 1.3.25.4, 1.4.26.1 through 1.4.26.4, 1.5.27.1 through 1.5.27.3, and 1.6.29.1 through 1.6.29.6 for the Apache HTTP Server allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.
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Analysis
by VulDB Data Team • 01/10/2022
The CVE-2013-6111 vulnerability represents a critical cross-site scripting flaw within the mod_pagespeed Apache module, affecting multiple version ranges from 0.x through 1.6.29.6. This module serves as a powerful optimization tool that automatically optimizes web pages by rewriting and compressing resources, making it a common component in many web server configurations. The vulnerability arises from insufficient input validation and output encoding mechanisms within the module's processing routines, creating a pathway for malicious actors to inject arbitrary web scripts or HTML content into web pages served by affected Apache servers.
The technical flaw manifests in the module's inability to properly sanitize user-supplied input data that flows through its optimization processes. When mod_pagespeed encounters certain web content that it needs to process or modify, the vulnerability allows attackers to inject malicious payloads that bypass normal security controls. This occurs because the module fails to implement proper context-aware encoding or validation before incorporating user data into generated web content. The unspecified vectors suggest that the vulnerability can be triggered through various input points within the module's functionality, including but not limited to query parameters, form submissions, or content manipulation features that the module handles during its optimization routines.
From an operational impact perspective, this vulnerability creates significant security risks for organizations running affected Apache servers with mod_pagespeed enabled. Attackers can leverage this flaw to execute malicious scripts in the context of a victim's browser, potentially leading to session hijacking, credential theft, or redirection to malicious websites. The vulnerability is particularly dangerous because mod_pagespeed is often deployed in production environments where it processes sensitive content, making it an attractive target for attackers seeking to exploit user sessions or gain unauthorized access to web applications. The attack vector requires no special privileges, making it accessible to any remote attacker who can influence input to the web server.
The vulnerability aligns with CWE-79, which specifically addresses cross-site scripting flaws in software applications, and demonstrates the importance of proper input validation and output encoding in web security. From an ATT&CK framework perspective, this vulnerability maps to techniques involving code injection and credential access, potentially enabling adversaries to establish persistent access through session manipulation or data exfiltration. Organizations should immediately implement mitigations including updating to patched versions of mod_pagespeed, implementing web application firewalls, and conducting thorough security assessments of their web server configurations to identify and remediate similar vulnerabilities in other modules or components.
The security implications extend beyond immediate exploitation as the vulnerability could enable attackers to establish footholds within web application environments, potentially leading to broader system compromises. Given that mod_pagespeed is designed to optimize web content delivery, the vulnerability could also be leveraged to manipulate performance metrics or inject malicious code into optimization processes, creating persistent threats that may evade traditional security monitoring. Organizations should prioritize patch management procedures and implement comprehensive monitoring to detect potential exploitation attempts, while also reviewing their web application security posture to address similar input validation weaknesses in other components of their infrastructure.