CVE-2009-4420 in Big-IP Protocol Security Manager
Summary
by MITRE
Buffer overflow in the bd daemon in F5 Networks BIG-IP Application Security Manager (ASM) 9.4.4 through 9.4.7 and 10.0.0 through 10.0.1, and Protocol Security Manager (PSM) 9.4.5 through 9.4.7 and 10.0.0 through 10.0.1, allows remote attackers to cause a denial of service (crash) via unknown vectors. NOTE: some of these details are obtained from third party information.
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Analysis
by VulDB Data Team • 05/03/2017
The vulnerability identified as CVE-2009-4420 represents a critical buffer overflow condition within the bd daemon component of F5 Networks BIG-IP Application Security Manager and Protocol Security Manager products. This flaw affects specific versions of the BIG-IP platform including ASM 9.4.4 through 9.4.7 and 10.0.0 through 10.0.1, as well as PSM 9.4.5 through 9.4.7 and 10.0.0 through 10.0.1. The vulnerability exists in the daemon process responsible for handling certain network protocol processing functions, making it a significant concern for network security infrastructure. The buffer overflow occurs when the daemon processes incoming network traffic without proper bounds checking, creating an exploitable condition that can be leveraged by remote attackers.
The technical implementation of this vulnerability stems from improper input validation within the bd daemon's protocol handling routines. When the daemon receives malformed or specially crafted network packets, it fails to properly validate the size of incoming data buffers before copying data into fixed-size memory regions. This classic buffer overflow condition allows attackers to overwrite adjacent memory locations, potentially leading to arbitrary code execution or system crash. The vulnerability's classification as a remote attack vector means that malicious actors can exploit this flaw from outside the network perimeter without requiring local access or authentication credentials. According to CWE standards, this represents a CWE-121: Stack-based Buffer Overflow, which is categorized under the broader weakness of insufficient boundary checking.
The operational impact of CVE-2009-4420 manifests primarily as a denial of service condition that can cause the affected BIG-IP systems to crash and become unavailable. When successfully exploited, the buffer overflow forces the bd daemon to terminate unexpectedly, resulting in complete service interruption for the application and protocol security services. This disruption affects critical network infrastructure components that protect enterprise applications and data, potentially leading to significant business continuity issues. The vulnerability's exploitation can occur through various network protocols that the daemon processes, making it particularly dangerous as attackers can target multiple communication channels. Organizations relying on F5 BIG-IP systems for security protection face substantial risk of service disruption that could compromise their overall security posture.
Mitigation strategies for CVE-2009-4420 should prioritize immediate patch deployment from F5 Networks, as the vendor has released security updates addressing this specific vulnerability. Organizations should implement network segmentation to limit exposure of affected systems and monitor network traffic for signs of exploitation attempts. The implementation of intrusion detection systems with signature-based detection capabilities can help identify potential exploitation attempts. Additionally, network administrators should consider disabling unnecessary protocol processing features within the affected daemons when possible. According to ATT&CK framework methodology, this vulnerability would be categorized under T1499.004: Endpoint Denial of Service, representing a specific technique for achieving denial of service through exploitation of software vulnerabilities. Regular security assessments and vulnerability management programs should include verification of patch compliance for all F5 BIG-IP systems to prevent exploitation of this and similar vulnerabilities.