CVE-2011-2060 in ASA
Summary
by MITRE
The platform-sw component on Cisco Adaptive Security Appliances (ASA) 5500 series devices with software 8.2 before 8.2(5.3), 8.3 before 8.3(2.20), and 8.4 before 8.4(2.1) does not properly handle non-ASCII characters in an interface description, which allows local users to cause a denial of service (reload without configuration) via a crafted description, aka Bug ID CSCtq50523.
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Analysis
by VulDB Data Team • 04/20/2017
The vulnerability identified as CVE-2011-2060 affects Cisco Adaptive Security Appliances (ASA) 5500 series devices operating with specific software versions, representing a critical flaw in the platform-sw component that handles interface descriptions. This issue stems from inadequate input validation mechanisms within the ASA software, specifically when processing non-ASCII character sequences in interface configuration fields. The vulnerability manifests as a failure to properly sanitize and process international character sets, creating a potential vector for malicious exploitation that could result in complete system disruption.
The technical flaw resides in the improper handling of character encoding within the platform-sw component, which is responsible for managing various platform-level configurations on ASA devices. When a local attacker crafts an interface description containing non-ASCII characters, the system fails to properly process these sequences, leading to a cascade of errors that ultimately results in the device performing an unauthorized reload operation. This behavior constitutes a classic buffer overflow or parsing error scenario where malformed input causes the system to crash and restart, effectively creating a denial of service condition that can be exploited to disrupt network security operations.
The operational impact of this vulnerability extends beyond simple service disruption, as it can result in complete loss of device configuration and potentially expose network infrastructure to extended periods of unavailability. The denial of service occurs through a reload operation that typically does not preserve current configurations, forcing administrators to reconfigure the device and potentially causing network outages. This vulnerability particularly affects organizations relying on ASA 5500 series appliances for network security, as the local nature of the attack means that any user with access to the device's interface configuration capabilities could exploit this flaw, making it a significant concern for network security management.
The vulnerability aligns with CWE-129, which addresses improper validation of input boundaries, and represents a specific implementation weakness in character set handling that allows malformed data to trigger system instability. From an ATT&CK perspective, this vulnerability maps to T1499.004, specifically targeting network denial of service through device reload operations. Organizations should implement immediate mitigation strategies including applying the relevant Cisco security patches, restricting local access to device configuration interfaces, and implementing monitoring controls to detect unauthorized configuration changes that might indicate exploitation attempts.
The remediation process requires organizations to upgrade their ASA software to versions that address the character handling flaw, specifically versions 8.2(5.3), 8.3(2.20), and 8.4(2.1) or later. Security teams should also implement network segmentation and access controls to limit local administrative access to these devices, reducing the attack surface for potential exploitation. Additionally, regular monitoring of device logs for configuration change patterns and system reload events should be established to detect potential exploitation attempts, as the vulnerability's impact directly affects network security infrastructure availability and operational continuity.