The Cisco Network Admission Control (NAC) 3.6.4.1 and earlier allows remote attackers to prevent installation of the Cisco Clean Access (CCA) Agent and bypass local and remote protection mechanisms by modifying (1) the HTTP User-Agent header or (2) the behavior of the TCP/IP stack. NOTE: the vendor has disputed the severity of this issue, stating that users cannot bypass authentication mechanisms.

Cisco Clean Access 3.5.5 and earlier on the Secure Smart Manager allows remote attackers to bypass authentication and cause a denial of service or upload files via direct requests to obsolete JSP files including (1) admin/uploadclient.jsp, (2) apply_firmware_action.jsp, and (3) file.jsp.

Cisco Clean Access (CCA) 3.3.0 to 3.3.9, 3.4.0 to 3.4.5, and 3.5.0 to 3.5.3 does not properly authenticate users when invoking API methods, which could allow remote attackers to bypass security checks, change the assigned role of a user, or disconnect users.