Cisco Security Advisory – A vulnerability in the malicious file detection and blocking features of Cisco Firepower System Software could allow an unauthenticated, remote attacker to bypass malware detection mechanisms on an affected system. The vulnerability is due to improper input validation of fields in HTTP headers. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected system. A successful exploit could allow the attacker to bypass malicious file detection or blocking policies that are configured for the system, which could allow malware to pass through the system undetected. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.