AAA Services used for 802.1x must be configured to use secure Extensible Authentication Protocol (EAP), such as EAP-TLS, EAP-TTLS, and PEAP.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-80901	SRG-APP-000516-AAA-000440	SV-95611r1_rule		Medium

Description
Additional new EAP methods/types are still being proposed. However, the three being considered secure are EAP-TLS, EAP-TTLS, and PEAP. PEAP is the preferred EAP type to be used in DoD for its ability to support a greater number of operating systems and its capability to transmit statement of health information, per NSA NAC study. Lightweight EAP (LEAP) is a CISCO proprietary protocol providing an easy-to-deploy one-password authentication. LEAP is vulnerable to dictionary attacks. A "man in the middle" can capture traffic, identify a password, and then use it to access a WLAN. LEAP is inappropriate and does not provide sufficient security for use on DOD networks. EAP-MD5 is functionally similar to CHAP and is susceptible to eavesdropping because the password credentials are sent as a hash (not encrypted). In addition, server administrators would be required to store unencrypted passwords on their servers violating other security policies. EAP-MD5 is inappropriate and does not provide sufficient security for use on DOD networks.

Description

Additional new EAP methods/types are still being proposed. However, the three being considered secure are EAP-TLS, EAP-TTLS, and PEAP. PEAP is the preferred EAP type to be used in DoD for its ability to support a greater number of operating systems and its capability to transmit statement of health information, per NSA NAC study. Lightweight EAP (LEAP) is a CISCO proprietary protocol providing an easy-to-deploy one-password authentication. LEAP is vulnerable to dictionary attacks. A "man in the middle" can capture traffic, identify a password, and then use it to access a WLAN. LEAP is inappropriate and does not provide sufficient security for use on DOD networks. EAP-MD5 is functionally similar to CHAP and is susceptible to eavesdropping because the password credentials are sent as a hash (not encrypted). In addition, server administrators would be required to store unencrypted passwords on their servers violating other security policies. EAP-MD5 is inappropriate and does not provide sufficient security for use on DOD networks.

STIG	Date
Authentication, Authorization, and Accounting Services (AAA) Security Requirements Guide	2019-12-12

Details

Check Text ( C-80639r1_chk )
Verify AAA Services used for 802.1x are configured to use secure EAP. Currently acceptable secure protocols are EAP-TLS, EAP-TTLS, and PEAP. If AAA Services used for 802.1x are not configured to use secure EAP, this is a finding.

Fix Text (F-87757r1_fix)
Configure AAA Services used for 802.1x to use secure EAP, such as EAP-TLS, EAP-TTLS, and PEAP.