CVE-2010-4680 in ASA
Summary
by MITRE
The WebVPN implementation on Cisco Adaptive Security Appliances (ASA) 5500 series devices with software before 8.2(3) permits the viewing of CIFS shares even when CIFS file browsing has been disabled, which allows remote authenticated users to bypass intended access restrictions via CIFS requests, aka Bug ID CSCsz80777.
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Analysis
by VulDB Data Team • 11/30/2024
The vulnerability described in CVE-2010-4680 represents a critical access control flaw within Cisco Adaptive Security Appliances running software versions prior to 8.2(3). This issue specifically affects the WebVPN implementation on ASA 5500 series devices, where the security controls fail to properly enforce CIFS file browsing restrictions. The flaw exists in the authentication and authorization mechanisms that govern how users interact with CIFS shares through the WebVPN interface, creating a pathway for unauthorized access to network resources that should remain protected.
The technical root cause of this vulnerability lies in the improper enforcement of access control policies within the WebVPN subsystem of the ASA device. When CIFS file browsing is disabled through configuration settings, the system should prevent users from accessing CIFS shares entirely. However, the flaw allows authenticated users to bypass these restrictions through specially crafted CIFS requests, effectively circumventing the intended security controls. This represents a classic case of insufficient authorization checking where the system fails to validate that users have proper permissions before granting access to CIFS resources, aligning with CWE-284 which addresses improper access control issues.
The operational impact of this vulnerability is significant for organizations relying on Cisco ASA devices for network security. Remote authenticated users who can establish WebVPN connections can exploit this flaw to access CIFS shares that should be restricted, potentially leading to data exposure, unauthorized file access, and privilege escalation within the network. This vulnerability undermines the fundamental security model of the ASA device by allowing lateral movement and information disclosure that bypasses the device's intended access control policies. The risk is particularly elevated in environments where sensitive data is stored on CIFS shares and where the WebVPN service is enabled for legitimate business purposes.
Organizations affected by this vulnerability should immediately implement the security patch provided by Cisco, which updates the ASA software to version 8.2(3) or later. Additionally, network administrators should review and tighten their WebVPN configurations to ensure that CIFS file browsing is properly disabled across all affected devices. The mitigation strategy should include monitoring for unauthorized CIFS access attempts and implementing network segmentation to limit the potential impact of successful exploitation. From a compliance perspective, this vulnerability would likely violate security standards such as those outlined in the NIST Cybersecurity Framework and could result in failed security audits. The ATT&CK framework would categorize this as a privilege escalation technique, specifically related to the use of legitimate credentials to access restricted network resources, potentially enabling further reconnaissance and lateral movement activities within the compromised network environment.