CVE-2013-5542 in ASA
Summary
by MITRE
Cisco Adaptive Security Appliance (ASA) Software 8.4 before 8.4(7.2), 8.7 before 8.7(1.8), 9.0 before 9.0(3.6), and 9.1 before 9.1(2.8) allows remote attackers to cause a denial of service (firewall-session disruption or device reload) via crafted ICMP packets, aka Bug ID CSCui77398.
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Analysis
by VulDB Data Team • 01/08/2022
The Cisco Adaptive Security Appliance ASA software contains a critical vulnerability that affects multiple versions including 8.4 before 8.4(7.2), 8.7 before 8.7(1.8), 9.0 before 9.0(3.6), and 9.1 before 9.1(2.8). This vulnerability manifests as a remote denial of service condition that can be triggered by sending specially crafted ICMP packets to the affected devices. The flaw represents a significant security weakness that could allow unauthorized actors to disrupt network operations and potentially cause complete device reloads, thereby compromising network availability and security posture.
The technical nature of this vulnerability stems from improper handling of ICMP packets within the ASA software processing pipeline. When the appliance receives malformed or specially constructed ICMP traffic, the processing logic fails to properly validate or sanitize the packet contents before attempting to establish or maintain firewall sessions. This inadequate input validation creates a condition where the device becomes vulnerable to exploitation through carefully crafted packet sequences that can cause the system to either disrupt existing firewall sessions or trigger a complete device reload. The vulnerability operates at the network protocol level, specifically targeting the ICMP protocol handler within the ASA's security processing framework.
The operational impact of this vulnerability extends beyond simple service disruption to encompass potential business continuity risks and security compromise. Network administrators may experience unexpected downtime as firewall sessions become disrupted, forcing network traffic to be dropped or rerouted through alternative paths. In severe cases, the device may require manual intervention to restore normal operation, as the reload process necessitates administrative access and potentially impacts network connectivity for extended periods. The remote nature of the attack means that adversaries can exploit this vulnerability from outside the network perimeter without requiring physical access or authentication credentials, making it particularly dangerous for organizations that rely on ASA appliances for network security.
Organizations affected by this vulnerability should prioritize immediate remediation through official Cisco software updates and patches. The recommended mitigation strategy involves upgrading to the latest software versions that address the specific ICMP handling flaws. Security teams should also implement network monitoring to detect anomalous ICMP traffic patterns that might indicate exploitation attempts. According to CWE classification, this vulnerability aligns with CWE-129, which addresses improper validation of input boundaries, and CWE-20, which covers input validation issues. From an ATT&CK framework perspective, this vulnerability maps to T1499.004, which covers network disruption attacks, and T1566.001, which involves social engineering through spearphishing. Organizations should also consider implementing network segmentation and access controls to limit exposure and establish defensive measures against potential exploitation attempts.