CVE-2020-3436: 
Cisco Adaptive Security Appliance (ASA) vulnerability analysis and mitigation

A vulnerability was identified in the web services interface of Cisco Adaptive Security Appliance (ASA) and Cisco Firepower Threat Defense (FTD) Software, tracked as CVE-2020-3436. The vulnerability was discovered in December 2019 and publicly disclosed on October 21, 2020. This security flaw affects the web services interface of both ASA and FTD software installations (CVE Mitre).

The vulnerability exists due to inefficient handling of large file writes to specific folders on the local file system. The severity of this vulnerability is rated as High with a CVSS base score of 8.6. The vulnerability is classified under CWE-434, relating to unrestricted file upload issues (Cisco Advisory).

A successful exploitation of this vulnerability could allow an unauthenticated, remote attacker to trigger a watchdog timeout by uploading arbitrary-sized files to specific folders on an affected device. This could result in an unexpected device reload, leading to a denial of service (DoS) condition (CVE Mitre).

The vulnerability can be exploited by an unauthenticated, remote attacker by uploading files to specific folders on the affected system. No user interaction is required for exploitation (Cisco Advisory).

Cisco has released software updates addressing this vulnerability. Users are advised to update to the latest version of the ASA and FTD software (Cisco Advisory).