Netgate pfSense sshguard Implementation Access Bypass Vulnerability



A vulnerability in Netgate pfSense could allow an unauthenticated, remote attacker to bypass security restrictions on a targeted system.

The vulnerability is due to inconsistencies related to blocking source IP addresses in connection with HTTPS authentications and failed SSH authentications. An attacker
could exploit this vulnerability by attempting to connect via one protocol and then with another protocol. A successful exploit could allow an attacker to bypass
intended security access restrictions.

Proof-of-concept (PoC) code that demonstrates an exploit of this vulnerability is publicly available.

Netgate has confirmed this vulnerability and has released updated software.

Security Impact Rating: High

CVE: CVE-2018-20799

Source:: Cisco Multivendor Vulnerability Alerts