Cisco Web Security Appliance HTTPS Packet Processing Denial of Service Vulnerability

A vulnerability in the web proxy framework of the Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker with the ability to negotiate a secure connection from within the trusted network to cause a denial of service (DoS) condition on the affected device.

The vulnerability is due to incorrect processing of HTTPS packets. An attacker could exploit this vulnerability by sending a malformed HTTPS request packet through the affected device. A successful exploit could allow an attacker to create a DoS condition, causing all requests traversing the WSA to be dropped. The condition is temporary and no manual intervention is required to restore functionality.

Cisco has released software updates that address this vulnerability. Workarounds that mitigate this vulnerability are not available.

This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160302-wsa[“https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160302-wsa”]