CVE-2022-41317 in Web Proxy
Summary
by MITRE • 12/26/2022
An issue was discovered in Squid 4.9 through 4.17 and 5.0.6 through 5.6. Due to inconsistent handling of internal URIs, there can be Exposure of Sensitive Information about clients using the proxy via an HTTPS request to an internal cache manager URL. This is fixed in 5.7.
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Analysis
by VulDB Data Team • 04/15/2025
The vulnerability identified as CVE-2022-41317 represents a critical information disclosure flaw affecting Squid proxy servers version 4.9 through 4.17 and 5.0.6 through 5.6. This issue stems from inconsistent handling of internal Uniform Resource Identifiers within the proxy infrastructure, creating a pathway for unauthorized exposure of sensitive client information. The vulnerability specifically manifests when HTTPS requests are made to internal cache manager URLs, allowing attackers to potentially extract confidential data about proxy users and their activities. The flaw exploits the improper management of internal URI structures that should remain isolated from external access, creating a security boundary violation that compromises proxy confidentiality. Organizations utilizing affected Squid versions face significant risks as this vulnerability enables attackers to gather sensitive information about client connections, user behavior patterns, and potentially other internal proxy operational details. The exposure occurs through the cache manager interface which is designed to provide administrative access but fails to properly validate or restrict access to internal URLs under certain conditions.
The technical implementation of this vulnerability involves the inconsistent processing of internal URIs within Squid's request handling pipeline. When an HTTPS request is made to an internal cache manager URL, the proxy's URI parsing and validation mechanisms fail to properly enforce access controls, allowing unauthorized access to information that should remain restricted. This flaw falls under the category of improper access control as defined by CWE-284, where insufficient validation of internal resource access creates opportunities for information disclosure. The vulnerability specifically impacts the cache manager interface which provides administrative functions but should not expose sensitive client information through external requests. The inconsistent handling occurs during the URI normalization and access control evaluation phases, where internal paths that should be restricted are not properly validated against external access attempts. This creates a scenario where legitimate administrative functions become accessible through external HTTPS requests, potentially exposing proxy cache statistics, client connection details, and other sensitive operational data.
The operational impact of CVE-2022-41317 extends beyond simple information disclosure to potentially enable more sophisticated attacks within a network environment. An attacker exploiting this vulnerability could gather intelligence about internal network structures, identify active client connections, and potentially map proxy usage patterns that could inform subsequent attacks. The exposure of client information through cache manager URLs could reveal user behavior, frequently accessed resources, and connection patterns that may aid in targeted attacks or social engineering efforts. This vulnerability particularly affects organizations that rely heavily on Squid proxy servers for network traffic management, as the exposure of client information could compromise privacy and potentially lead to further security breaches. The impact is compounded when organizations use Squid as part of larger security infrastructures where proxy data may correlate with other security events or threat intelligence. The vulnerability's presence in multiple versions of Squid creates widespread exposure across different deployment scenarios, making it particularly concerning for organizations with legacy systems or those that have not yet upgraded to the fixed version.
Organizations should immediately implement mitigations to address this vulnerability by upgrading to Squid version 5.7 or the latest available patch release for their affected version. The upgrade process should include thorough testing of the new version in a staging environment to ensure compatibility with existing proxy configurations and network policies. Network administrators should also review and tighten access controls to cache manager interfaces, implementing additional restrictions beyond the default configurations. This includes configuring proper authentication mechanisms and limiting access to cache manager URLs to authorized administrative personnel only. The implementation of network segmentation and firewall rules can help restrict access to internal proxy management interfaces from external networks. Security monitoring should be enhanced to detect unusual access patterns to cache manager URLs, particularly those that might indicate exploitation attempts. Organizations should also conduct comprehensive vulnerability assessments to identify any other potential access control issues within their proxy infrastructure and review their incident response procedures to ensure readiness for potential exploitation of this vulnerability. This remediation approach aligns with ATT&CK framework techniques related to privilege escalation and credential access, as the vulnerability enables unauthorized access to information that could be used for further compromise.