CVE-2008-1612 in Proxy
Summary
by MITRE
The arrayShrink function (lib/Array.c) in Squid 2.6.STABLE17 allows attackers to cause a denial of service (process exit) via unknown vectors that cause an array to shrink to 0 entries, which triggers an assert error. NOTE: this issue is due to an incorrect fix for CVE-2007-6239.
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Analysis
by VulDB Data Team • 06/01/2025
The vulnerability described in CVE-2008-1612 represents a critical denial of service flaw within the Squid web proxy software version 2.6.STABLE17. This issue manifests in the arrayShrink function located in the lib/Array.c source file, where an improper handling of array size reduction leads to process termination. The vulnerability was introduced as an incorrect remediation for a previous security issue, CVE-2007-6239, demonstrating how security fixes can sometimes introduce new weaknesses that may be exploited by malicious actors.
The technical mechanism behind this vulnerability involves the arrayShrink function's failure to properly validate array boundaries when attempting to reduce array size to zero entries. When an attacker can manipulate input data or network conditions to trigger this specific code path, the function executes an assertion error that causes the Squid process to terminate abruptly. This behavior constitutes a classic denial of service attack vector where legitimate service availability is compromised through controlled process termination. The flaw operates at the software level within the proxy's core functionality, making it particularly dangerous as it can disrupt web proxy services that many organizations depend upon for network traffic management and caching operations.
The operational impact of this vulnerability extends beyond simple service disruption to potentially affect network infrastructure reliability and availability. Organizations relying on Squid as their primary web proxy solution face significant risk when this vulnerability exists in their environment, as attackers can reliably cause service outages without requiring elevated privileges or complex exploitation techniques. The vulnerability's classification aligns with CWE-682, which addresses incorrect arithmetic operations and improper handling of data boundaries, while also mapping to ATT&CK technique T1499.100 for endpoint denial of service through process termination. Network administrators may observe sudden proxy service failures, increased error rates, and potential cascading effects on downstream systems that depend on uninterrupted proxy functionality.
Mitigation strategies for this vulnerability require immediate attention through software patching and updates to the Squid proxy software. Organizations should prioritize upgrading to versions that properly address both CVE-2008-1612 and its underlying cause CVE-2007-6239 to prevent exploitation. Additionally, implementing network monitoring to detect unusual patterns in proxy service availability and establishing redundant proxy infrastructure can help minimize the impact of such attacks. System administrators should also consider implementing input validation controls and access restrictions to limit potential attack surface while maintaining service availability. The vulnerability serves as a reminder of the importance of thorough regression testing when applying security patches and the potential risks associated with incomplete or incorrect security fixes.