Nutanix AOS must implement replay-resistant authentication mechanisms for network access to privileged accounts.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-254205	NUTX-OS-001190	SV-254205r846703_rule		Medium

Description
A replay attack may enable an unauthorized user to gain access to the operating system. Authentication sessions between the authenticator and the operating system validating the user credentials must not be vulnerable to a replay attack. An authentication process resists replay attacks if it is impractical to achieve a successful authentication by recording and replaying a previous authentication message. A privileged account is any information system account with authorizations of a privileged user. Techniques used to address this include protocols using nonces (e.g., numbers generated for a specific one-time use) or challenges (e.g., TLS, WS_Security). Additional techniques include time-synchronous or challenge-response one-time authenticators. Satisfies: SRG-OS-000112-GPOS-00057, SRG-OS-000113-GPOS-00058

Description

A replay attack may enable an unauthorized user to gain access to the operating system. Authentication sessions between the authenticator and the operating system validating the user credentials must not be vulnerable to a replay attack. An authentication process resists replay attacks if it is impractical to achieve a successful authentication by recording and replaying a previous authentication message. A privileged account is any information system account with authorizations of a privileged user. Techniques used to address this include protocols using nonces (e.g., numbers generated for a specific one-time use) or challenges (e.g., TLS, WS_Security). Additional techniques include time-synchronous or challenge-response one-time authenticators. Satisfies: SRG-OS-000112-GPOS-00057, SRG-OS-000113-GPOS-00058

STIG	Date
Nutanix AOS 5.20.x OS Security Technical Implementation Guide	2022-08-24

Details

Check Text ( C-57690r846701_chk )
Confirm Nutanix AOS has SSH loaded and active. $ sudo systemctl status sshd sshd.service - OpenSSH server daemon Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled) Active: active (running) since Tue 2015-11-17 15:17:22 EST; 4 weeks 0 days ago Main PID: 1348 (sshd) CGroup: /system.slice/sshd.service 1053 /usr/sbin/sshd -D If "sshd" does not show a status of "active" and "running", this is a finding. If the "SSH server" package is not installed, this is a finding.

Check Text ( C-57690r846701_chk )

Confirm Nutanix AOS has SSH loaded and active.

$ sudo systemctl status sshd
sshd.service - OpenSSH server daemon
Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled)
Active: active (running) since Tue 2015-11-17 15:17:22 EST; 4 weeks 0 days ago
Main PID: 1348 (sshd)
CGroup: /system.slice/sshd.service
1053 /usr/sbin/sshd -D

If "sshd" does not show a status of "active" and "running", this is a finding.

If the "SSH server" package is not installed, this is a finding.

Fix Text (F-57641r846702_fix)
Configure SSH on Nutanix AOS by running the following command: $ sudo salt-call state.sls security/CVM/sshdCVM