A critical vulnerability in Session Initiation Protocol (SIP) of Cisco ASA and FTD software that allows an unauthenticated remote attacker to crash and reload the device. The vulnerability occurs due to the improper handling of SIP traffic. Cisco says the security update to address the vulnerability is not yet available and at the time there is no workaround for this vulnerability. Vulnerability affects Cisco ASA Software Release 9.4 and later and Cisco FTD Software Release 6.0 and later if SIP inspection is enabled.”]
Source: https://gbhackers.com/hackers-exploit-cisco-zero-day/