Cisco Email Security Appliance Drop Bypass Vulnerability

A vulnerability in the configured security policies, including drop email filtering, in Cisco AsyncOS for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass a configured drop filter by using an email with a corrupted attachment.

The vulnerability is due to improper error handling. An attacker could exploit this vulnerability by sending an email message with a corrupted attachment. A successful exploit could allow the attacker to bypass a configured drop filter.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161026-esa5[“https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161026-esa5”]