CVE-2024-20268 in ASA
Summary
by MITRE • 10/23/2024
A vulnerability in the Simple Network Management Protocol (SNMP) feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker to cause an unexpected reload of the device.
This vulnerability is due to insufficient input validation of SNMP packets. An attacker could exploit this vulnerability by sending a crafted SNMP request to an affected device using IPv4 or IPv6. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability affects all versions of SNMP (versions 1, 2c, and 3) and requires a valid SNMP community string or valid SNMPv3 user credentials.
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Analysis
by VulDB Data Team • 10/25/2024
The vulnerability identified as CVE-2024-20268 represents a critical denial of service weakness within Cisco's network security infrastructure, specifically affecting the Simple Network Management Protocol implementation in Adaptive Security Appliance and Firepower Threat Defense software solutions. This flaw resides in the fundamental packet processing logic where insufficient validation mechanisms fail to properly sanitize incoming SNMP communications, creating an exploitable condition that can be leveraged by remote attackers. The vulnerability impacts all SNMP protocol versions including v1, v2c, and v3, demonstrating the widespread nature of this input validation failure across the SNMP ecosystem. The security implications extend beyond simple service disruption as this weakness can be triggered through authenticated access, requiring only valid community strings or SNMPv3 credentials to establish the necessary privileges for exploitation.
The technical exploitation of this vulnerability occurs through the manipulation of SNMP packet structures that bypass proper input validation checks within the ASA and FTD software implementations. When an attacker crafts and sends specifically formatted SNMP requests to the targeted device, the malformed packets trigger an unexpected state within the device's processing pipeline, ultimately leading to an uncontrolled system reload. This behavior constitutes a classic denial of service attack vector where the attacker can repeatedly induce system restarts, effectively rendering the network security appliance unavailable to protect the network infrastructure. The attack can be executed over both IPv4 and IPv6 protocols, expanding the attack surface and making the vulnerability applicable across modern network environments. The requirement for valid authentication credentials means that this vulnerability cannot be exploited by anonymous attackers, but it does represent a significant risk when credentials are compromised or when legitimate administrative access is misused.
From an operational perspective, the impact of CVE-2024-20268 extends far beyond simple service interruption as the unexpected device reloads can disrupt critical network security functions and potentially create windows of vulnerability during system recovery periods. Network administrators face the challenge of maintaining security posture while addressing this vulnerability, as the exploit can be used to create sustained denial of service conditions that may go unnoticed until significant service degradation occurs. The vulnerability affects the availability aspect of the CIA triad, specifically targeting the system's ability to maintain continuous operation and service delivery. Organizations implementing Cisco ASA and FTD solutions must consider the potential for cascading failures if multiple devices are affected simultaneously, as the reload events could disrupt network segmentation, logging capabilities, and overall security monitoring functions. This vulnerability also aligns with ATT&CK technique T1499.004 for network denial of service and CWE-20 for improper input validation, demonstrating how fundamental security flaws can create substantial operational risks.
Mitigation strategies for CVE-2024-20268 should prioritize immediate implementation of software updates from Cisco that address the specific input validation issues within SNMP processing. Network segmentation and access control measures should be enhanced to limit SNMP access to only trusted administrative networks, reducing the attack surface for potential exploitation. Organizations should implement monitoring solutions that can detect unusual reload patterns or SNMP traffic anomalies that might indicate exploitation attempts. The use of SNMPv3 with strong authentication and encryption mechanisms should be prioritized over SNMPv1 and v2c where possible, as the enhanced security features provide additional protection layers. Network administrators should also consider implementing intrusion detection systems that can identify and alert on suspicious SNMP packet structures that match the vulnerability characteristics. Regular security assessments and vulnerability scanning should be conducted to ensure that all SNMP-enabled devices are properly patched and configured according to security best practices, with particular attention to the SNMP configuration settings that control access and authentication parameters.