CVE-2009-2865 in IOS
Summary
by MITRE
Buffer overflow in the login implementation in the Extension Mobility feature in the Unified Communications Manager Express (CME) component in Cisco IOS 12.4XW, 12.4XY, 12.4XZ, and 12.4YA allows remote attackers to execute arbitrary code or cause a denial of service via crafted HTTP requests, aka Bug ID CSCsq58779.
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Analysis
by VulDB Data Team • 03/30/2025
The vulnerability described in CVE-2009-2865 represents a critical buffer overflow condition within the Extension Mobility feature of Cisco Unified Communications Manager Express running on specific IOS versions. This flaw exists in the login implementation mechanism that processes HTTP requests, creating an exploitable condition that can be leveraged by remote attackers without requiring authentication. The affected software versions include IOS 12.4XW, 12.4XY, 12.4XZ, and 12.4YA, which are part of Cisco's unified communications infrastructure designed for small to medium business environments. The vulnerability specifically targets the handling of HTTP requests within the Extension Mobility extension, which allows users to access their phone settings from any phone within the network.
The technical exploitation of this buffer overflow occurs when the system processes crafted HTTP requests containing maliciously formatted data that exceeds the allocated buffer space in the login implementation. This overflow can overwrite adjacent memory locations, potentially allowing attackers to inject and execute arbitrary code with the privileges of the affected process. The vulnerability manifests in the way the system handles user authentication requests through the Extension Mobility feature, where insufficient input validation and bounds checking enables attackers to manipulate memory structures. According to CWE classification, this vulnerability maps to CWE-121, which describes stack-based buffer overflow conditions, and CWE-787, which covers out-of-bounds write vulnerabilities. The attack vector is remote and does not require any special privileges, making it particularly dangerous as it can be exploited from anywhere on the network.
The operational impact of this vulnerability extends beyond simple denial of service scenarios, as successful exploitation can result in complete system compromise and unauthorized access to sensitive communication infrastructure. Organizations using affected Cisco IOS versions may experience unauthorized access to their unified communications systems, potentially leading to eavesdropping on voice communications, manipulation of phone settings, or even complete system takeover. The denial of service aspect can disrupt critical business communications, affecting productivity and potentially causing financial losses. Attackers can leverage this vulnerability to establish persistent access points within the network, using the compromised system as a foothold for further attacks. The vulnerability's presence in the Extension Mobility feature particularly impacts organizations that rely on mobile phone access and remote worker capabilities, as this functionality is designed to allow users to access their phone profiles from any device.
Mitigation strategies for CVE-2009-2865 require immediate implementation of software updates and patches provided by Cisco to address the buffer overflow condition. Organizations should apply the relevant security patches from Cisco's official advisory, which typically include fixes for the specific buffer overflow in the Extension Mobility login implementation. Network segmentation and access control measures should be implemented to limit exposure of affected systems to untrusted networks, particularly by restricting HTTP access to the vulnerable component. Monitoring network traffic for suspicious HTTP requests and implementing intrusion detection systems can help identify exploitation attempts. The ATT&CK framework categorizes this vulnerability under T1210 - Exploitation of Remote Services and T1072 - Software Deployment Tools, as attackers may leverage this weakness to establish persistent access and deploy additional malicious tools. Regular security assessments and vulnerability scanning should be conducted to identify any remaining instances of the vulnerable software versions, while network administrators should disable unnecessary services and features to reduce the attack surface. Additionally, implementing proper input validation and bounds checking mechanisms in custom applications that interact with the affected system can provide additional protection layers against similar vulnerabilities.