CVE-2011-0951 in Secure Access Control System
Summary
by MITRE
The web-based management interface in Cisco Secure Access Control System (ACS) 5.1 before 5.1.0.44.6 and 5.2 before 5.2.0.26.3 allows remote attackers to change arbitrary user passwords via unspecified vectors, aka Bug ID CSCtl77440.
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Analysis
by VulDB Data Team • 01/17/2025
The vulnerability identified as CVE-2011-0951 affects Cisco Secure Access Control System versions 5.1 before 5.1.0.44.6 and 5.2 before 5.2.0.26.3, specifically targeting the web-based management interface. This issue represents a critical authorization flaw that enables remote attackers to manipulate user credentials without proper authentication. The vulnerability resides within the access control mechanisms of the system's administrative web portal, creating a pathway for unauthorized privilege escalation and credential compromise. The unspecified vectors suggest that the flaw may be exploitable through multiple attack surfaces within the web interface, making it particularly concerning for security professionals.
This vulnerability directly maps to CWE-284, which describes improper access control in software systems. The flaw allows attackers to change arbitrary user passwords, effectively bypassing the authentication and authorization controls that should protect user accounts within the Cisco ACS environment. The attack vector is particularly dangerous because it operates over the network without requiring local system access or valid credentials, making it an attractive target for remote exploitation. The vulnerability essentially provides a backdoor mechanism for attackers to modify user accounts, potentially gaining persistent access to the network infrastructure managed by the ACS system.
The operational impact of this vulnerability extends beyond simple credential theft, as it enables attackers to establish persistent access within the network environment. Once an attacker successfully exploits this vulnerability, they can modify user accounts to create unauthorized access points, potentially compromising the entire access control system. The implications are severe for organizations relying on Cisco ACS for network security, as this vulnerability undermines the fundamental security model of the system. The ability to change arbitrary user passwords means that attackers can escalate privileges, create new administrative accounts, or disable legitimate user access, leading to potential network-wide compromise.
Organizations should immediately implement mitigations including patching to the latest available versions of Cisco Secure Access Control System, as specified in the vendor advisories. Network segmentation and firewall rules should be implemented to restrict access to the web-based management interface to trusted administrative networks only. Additionally, monitoring for unusual authentication activities and user account modifications should be enhanced to detect potential exploitation attempts. The vulnerability demonstrates the critical importance of maintaining up-to-date security patches and implementing defense-in-depth strategies. Security teams should also consider implementing multi-factor authentication for administrative access and regular security assessments of network access control systems to prevent similar vulnerabilities from remaining undetected in production environments.