CVE-2016-1379 in ASA
Summary
by MITRE
Cisco Adaptive Security Appliance (ASA) Software 9.0 through 9.5.1 mishandles IPsec error processing, which allows remote authenticated users to cause a denial of service (memory consumption) via crafted (1) LAN-to-LAN or (2) Remote Access VPN tunnel packets, aka Bug ID CSCuv70576.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 10/14/2024
The vulnerability identified as CVE-2016-1379 affects Cisco Adaptive Security Appliance (ASA) Software versions 9.0 through 9.5.1, representing a critical flaw in the IPsec error handling mechanisms of these network security devices. This vulnerability specifically targets the processing of IPsec packets within the ASA's VPN functionality, creating a condition where authenticated remote attackers can exploit improper error handling to consume excessive system memory. The flaw manifests when the ASA processes malformed or crafted IPsec packets that should trigger error conditions, but instead cause the device to continuously allocate memory resources without proper cleanup, leading to gradual system degradation and eventual denial of service.
The technical nature of this vulnerability stems from the ASA's failure to properly manage memory allocation during IPsec packet processing errors. When legitimate IPsec packets are received that contain malformed headers or invalid parameters, the ASA software should gracefully handle these errors and release associated memory resources. However, the implementation contains a memory leak condition where the system fails to properly deallocate memory that was allocated during error processing, particularly in LAN-to-LAN and Remote Access VPN tunnel contexts. This issue falls under the CWE-401 category of "Improper Release of Memory Before Removing Last Reference" and represents a classic memory management flaw that can be exploited through network-based attacks.
The operational impact of this vulnerability extends beyond simple denial of service, as it can severely compromise the availability and reliability of network security services provided by the affected ASA devices. Attackers who can authenticate to the ASA system can repeatedly send crafted IPsec packets that trigger the memory consumption behavior, potentially causing the device to become unresponsive or crash entirely. This creates a significant risk for organizations relying on ASA appliances for their network security infrastructure, as the attack can be executed remotely with minimal privileges required for authentication. The vulnerability affects both LAN-to-LAN and Remote Access VPN configurations, making it particularly dangerous as it can impact different types of secure connections within the same network infrastructure.
Organizations should implement immediate mitigations including applying the latest Cisco security patches and updates that address this specific memory leak condition in the IPsec error handling code. Network administrators should also consider implementing traffic filtering rules to limit the types of IPsec packets that can reach the ASA devices, particularly those that might trigger the vulnerable error conditions. Monitoring systems should be enhanced to detect unusual memory consumption patterns and potential exploitation attempts. The ATT&CK framework categorizes this vulnerability under T1499.004 for "Endpoint Denial of Service" and T1566.001 for "Phishing" in the context of initial access, though the primary attack vector is through authenticated network traffic. Additionally, implementing network segmentation and reducing the attack surface by disabling unnecessary VPN services can help mitigate the risk of exploitation.