CVE-2002-1153 in WebSphere Application Server
Summary
by MITRE
IBM Websphere 4.0.3 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via an HTTP request with long HTTP headers, such as "Host".
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Analysis
by VulDB Data Team • 09/08/2025
The vulnerability identified as CVE-2002-1153 affects IBM Websphere Application Server version 4.0.3, representing a critical security flaw that enables remote attackers to compromise system availability and potentially execute malicious code. This issue stems from inadequate input validation mechanisms within the web server's HTTP request processing pipeline, specifically when handling HTTP headers with excessive length. The vulnerability manifests when an attacker crafts an HTTP request containing elongated header values, particularly the "Host" header, which triggers buffer overflow conditions or memory corruption within the application server's processing routines.
The technical implementation of this vulnerability leverages the server's failure to properly validate or limit the length of incoming HTTP headers during request parsing. When the Websphere server receives an HTTP request containing oversized header content, the parsing logic fails to enforce reasonable length constraints, leading to memory allocation issues that can result in application crashes or unpredictable behavior. This flaw falls under the Common Weakness Enumeration category of buffer overflow conditions, specifically categorized as CWE-121, which describes heap-based buffer overflow vulnerabilities that occur when insufficient bounds checking is performed on buffer operations. The vulnerability operates at the application layer of the network stack, making it particularly dangerous as it can be exploited without requiring any authentication or prior access to the system.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enable remote code execution, making it a severe threat to system integrity and availability. An attacker exploiting this vulnerability can cause the Websphere application server to crash repeatedly, leading to sustained service disruption that can affect business operations and customer access to applications hosted on the server. The possibility of arbitrary code execution adds another dimension of risk, as successful exploitation could allow attackers to gain control over the server's execution environment, potentially leading to complete system compromise. This vulnerability particularly affects organizations relying on older versions of IBM Websphere, as version 4.0.3 was released during a period when security practices were less mature and comprehensive input validation was not as rigorously implemented.
Mitigation strategies for this vulnerability require immediate attention from system administrators and security teams responsible for maintaining IBM Websphere installations. The primary recommended approach involves applying the vendor-provided security patches and updates that address the buffer overflow conditions in the HTTP header processing logic. Organizations should also implement network-level protections such as rate limiting and header length restrictions through firewalls or reverse proxies to prevent exploitation attempts before they reach the vulnerable application server. Additionally, implementing proper input validation mechanisms within the application layer can provide defense-in-depth protection against similar vulnerabilities. The vulnerability aligns with ATT&CK technique T1499.004 which covers network denial of service attacks, and represents a classic example of how insufficient input validation can lead to critical security weaknesses in enterprise web applications. Regular security assessments and vulnerability scanning should be conducted to identify other potential buffer overflow conditions that may exist in legacy systems, as this vulnerability demonstrates the importance of maintaining updated security practices even in older software environments.