IBM z/OS SNTP daemon (SNTPD) permission bits must be properly configured.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-223551	ACF2-OS-000150	SV-223551r853543_rule		Medium

Description
Inaccurate time stamps make it more difficult to correlate events and can lead to an inaccurate analysis. Determining the correct time, a particular event occurred on a system is critical when conducting forensic analysis and investigating system events. Sources outside the configured acceptable allowance (drift) may be inaccurate. Synchronizing internal information system clocks provides uniformity of time stamps for information systems with multiple system clocks and systems connected over a network. Organizations should consider endpoints that may not have regular access to the authoritative time server (e.g., mobile, teleworking, and tactical endpoints).

Description

Inaccurate time stamps make it more difficult to correlate events and can lead to an inaccurate analysis. Determining the correct time, a particular event occurred on a system is critical when conducting forensic analysis and investigating system events. Sources outside the configured acceptable allowance (drift) may be inaccurate. Synchronizing internal information system clocks provides uniformity of time stamps for information systems with multiple system clocks and systems connected over a network. Organizations should consider endpoints that may not have regular access to the authoritative time server (e.g., mobile, teleworking, and tactical endpoints).

STIG	Date
IBM z/OS ACF2 Security Technical Implementation Guide	2022-09-29

Details

Check Text ( C-25224r500788_chk )
From the ISPF Command Shell enter: cd /usr/sbin ls -al If the following File permission and user Audit Bits are true, this is not a finding. /usr/sbin/sntpd 1740 faf The following represents a hierarchy for permission bits from least restrictive to most restrictive: 7 rwx (least restrictive) 6 rw- 3 -wx 2 -w- 5 r-x 4 r-- 1 --x 0 --- (most restrictive) The possible audit bits settings are as follows: f log for failed access attempts a log for failed and successful access - no auditing

Check Text ( C-25224r500788_chk )

From the ISPF Command Shell enter:
cd /usr/sbin
ls -al

If the following File permission and user Audit Bits are true, this is not a finding.

/usr/sbin/sntpd 1740 faf

The following represents a hierarchy for permission bits from least restrictive to most restrictive:

7 rwx (least restrictive)
6 rw-
3 -wx
2 -w-
5 r-x
4 r--
1 --x
0 --- (most restrictive)

The possible audit bits settings are as follows:
f log for failed access attempts
a log for failed and successful access
- no auditing

Fix Text (F-25212r500789_fix)
With the assistance of a systems programmer with UID(0) and/or SUPERUSER access, configure the UNIX permission bits and user audit bits on the SNTPD to conform to the specifications below: /usr/sbin/sntpd 1740 faf