A vulnerability in the email message filtering feature of Cisco AsyncOS for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to cause an ESA to fail to detect and act upon a specific type of file that is attached to an email message.
The vulnerability is due to improper application of message filtering rules to email attachments that contain a specific type of file and are submitted to an affected appliance. An attacker could exploit this vulnerability by sending an email message with a crafted attachment to an affected appliance. A successful exploit could allow the attacker to cause the ESA to fail to detect and act upon possible malware in the email attachment.
Cisco has not released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
This advisory is available at the following link: http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160727-esa["http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160727-esa"]