CVE-2012-0256 in Traffic Server
Summary
by MITRE
Apache Traffic Server 2.0.x and 3.0.x before 3.0.4 and 3.1.x before 3.1.3 does not properly allocate heap memory, which allows remote attackers to cause a denial of service (daemon crash) via a long HTTP Host header.
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Analysis
by VulDB Data Team • 03/22/2021
The vulnerability identified as CVE-2012-0256 represents a heap memory allocation flaw within Apache Traffic Server versions 2.0.x through 3.0.3 and 3.1.x through 3.1.2. This issue stems from insufficient input validation mechanisms when processing HTTP Host headers, creating a condition where maliciously crafted header values can trigger improper memory handling. The flaw manifests as a buffer overflow or memory corruption scenario that ultimately leads to daemon termination, effectively causing a denial of service condition for legitimate users. This vulnerability specifically impacts the HTTP request processing pipeline where the server attempts to store and manipulate the Host header value in memory without adequate bounds checking.
The technical exploitation of this vulnerability occurs when a remote attacker sends an HTTP request containing an excessively long Host header value to the affected Apache Traffic Server instance. The server's memory allocation routines fail to properly handle the oversized input, resulting in heap corruption that causes the daemon process to crash and restart. This memory management failure operates at the application layer and requires no authentication or specialized privileges to exploit, making it particularly dangerous for publicly accessible web proxies or cache servers. The vulnerability is classified under CWE-122, which describes improper restriction of operations within the bounds of a memory buffer, and aligns with ATT&CK technique T1499.004 for network denial of service attacks.
The operational impact of CVE-2012-0256 extends beyond simple service disruption, as it can be leveraged to create persistent availability issues for organizations relying on Apache Traffic Server for content delivery or proxy services. Network administrators may experience frequent daemon restarts, leading to increased system overhead and potential performance degradation. The vulnerability affects organizations that deploy Apache Traffic Server as a caching proxy or load balancer, where the daemon crash can cascade into broader service availability problems. Additionally, the exploit's simplicity means it can be easily automated, potentially allowing for sustained denial of service attacks that could overwhelm system monitoring and recovery mechanisms. Organizations with high-traffic websites or those serving as edge servers are particularly vulnerable to this attack vector.
Mitigation strategies for CVE-2012-0256 focus on both immediate patching and operational safeguards. The primary solution involves upgrading to Apache Traffic Server versions 3.0.4 or 3.1.3, which contain the necessary memory allocation fixes and input validation improvements. Organizations should implement network-level filtering to limit the length of HTTP Host headers at perimeter devices, effectively preventing malicious requests from reaching the vulnerable server. Additionally, deploying intrusion prevention systems with signature-based detection capabilities can help identify and block exploitation attempts. System administrators should also consider implementing rate limiting and connection throttling mechanisms to reduce the impact of potential attacks. The vulnerability demonstrates the importance of proper memory management practices and input validation, aligning with security best practices outlined in the OWASP Top Ten and NIST cybersecurity guidelines for preventing buffer overflow conditions in web applications.