cifs-ao in the CIFS optimization functionality on Cisco Wide Area Application Service (WAAS) and Virtual WAAS (vWAAS) devices 5.x before 5.3.5d and 5.4 and 5.5 before 5.5.3 allows remote attackers to cause a denial of service (resource consumption and device reload) via crafted network traffic, aka Bug ID CSCus85330.