SB2020111223 - Authenticatoin bypass in Pan-OS GlobalProtect SSL VPN

Description

This security bulletin contains information about 1 vulnerability.

1) Improper Authentication (CVE-ID: CVE-2020-2050)

CWE-ID: CWE-287 - Improper Authentication

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to an error in when processing authentication requests in the GlobalProtect SSL VPN component of Palo Alto Networks PAN-OS software that allows an attacker to bypass all client certificate checks with an invalid certificate. A remote attacker can successfully authenticate as any user and gain access to restricted VPN network resources when the gateway or portal is configured to rely entirely on certificate-based authentication.

Impacted features that use SSL VPN with client certificate verification are:

In configurations where client certificate verification is used in conjunction with other authentication methods, the protections added by the certificate check are ignored as a result of this issue.

Remediation

Install update from vendor's website.

References

• https://security.paloaltonetworks.com/CVE-2020-2050