Palo Alto Networks Security Advisories / CVE-2020-2002

CVE-2020-2002 PAN-OS: Spoofed Kerberos key distribution center authentication bypass

047910
Severity 8.1 · HIGH
Attack Vector NETWORK
Scope UNCHANGED
Attack Complexity HIGH
Confidentiality Impact HIGH
Privileges Required NONE
Integrity Impact HIGH
User Interaction NONE
Availability Impact HIGH

Description

An authentication bypass by spoofing vulnerability exists in the authentication daemon and User-ID components of Palo Alto Networks PAN-OS by failing to verify the integrity of the Kerberos key distribution center (KDC) before authenticating users. This affects all forms of authentication that use a Kerberos authentication profile. A man-in-the-middle type of attacker with the ability to intercept communication between PAN-OS and KDC can login to PAN-OS as an administrator.

This issue affects:

PAN-OS 7.1 versions earlier than 7.1.26;

PAN-OS 8.1 versions earlier than 8.1.13;

PAN-OS 9.0 versions earlier than 9.0.6;

All version of PAN-OS 8.0.

Product Status

VersionsAffectedUnaffected
PAN-OS 9.0< 9.0.6>= 9.0.6
PAN-OS 8.1< 8.1.13>= 8.1.13
PAN-OS 8.08.0.*
PAN-OS 7.1< 7.1.26>= 7.1.26

Severity:HIGH

CVSSv3.1 Base Score:8.1 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H)

Weakness Type

CWE-290 Authentication Bypass by Spoofing

Solution

This issue is fixed in PAN-OS 7.1.26, PAN-OS 8.1.13, PAN-OS 9.0.6, and all later PAN-OS versions.

PAN-OS 8.0 is now end-of-life as of October 31, 2019, and is no longer covered by our Product Security Assurance policies.

Workarounds and Mitigations

Ensure that PAN-OS communicates to Kerberos server over a secured network with access restricted to trusted users.

Please review the Best Practices for Securing Administrative Access in the PAN-OS technical documentation, available at: https://docs.paloaltonetworks.com.

Acknowledgments

Palo Alto Networks would like to thank Yoav Iellin, Yaron Kassner, and Rotem Zach from Silverfort for discovering and reporting this issue.

Timeline

Initial publication
© 2022 Palo Alto Networks, Inc. All rights reserved.