Cisco Asa 5520 Firmware

A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) handler of Cisco Firepower Threat Defense (FTD) Software when running on the Cisco Firepower 1000 Series platform could allow an unauthenticated, remote attacker to trigger a denial of service (DoS) condition on an affected device. The vulnerability is due to a communication error between internal functions. An attacker could exploit this vulnerability by sending a crafted SSL/TLS message to an affected device. A successful exploit could allow the attacker to cause a buffer underrun, which leads to a crash. The crash causes the affected device to reload.

A vulnerability in the Kerberos authentication feature of Cisco Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to impersonate the Kerberos key distribution center (KDC) and bypass authentication on an affected device that is configured to perform Kerberos authentication for VPN or local device access. The vulnerability is due to insufficient identity verification of the KDC when a successful authentication response is received. An attacker could exploit this vulnerability by spoofing the KDC server response to the ASA device. This malicious response would not have been authenticated by the KDC. A successful attack could allow an attacker to bypass Kerberos authentication.

A vulnerability in the Cisco ASA that could allow a remote attacker to successfully authenticate using the Cisco AnyConnect VPN client if the Secondary Authentication type is LDAP and the password is left blank, providing the primary credentials are correct. The vulnerabilities is due to improper input validation of certain parameters passed to the affected software. An attacker must have the correct primary credentials in order to successfully exploit this vulnerability.