Check: RHEL-07-030780
Red Hat Enterprise Linux 7 STIG:
RHEL-07-030780
(in versions v3 r14 through v3 r8)
Title
The Red Hat Enterprise Linux operating system must audit all uses of the ssh-keysign command. (Cat II impact)
Discussion
Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information. At a minimum, the organization must audit the full-text recording of privileged ssh commands. The organization must maintain audit trails in sufficient detail to reconstruct events to determine the cause and impact of compromise. When a user logs on, the auid is set to the uid of the account that is being authenticated. Daemons are not user sessions and have the loginuid set to -1. The auid representation is an unsigned 32-bit integer, which equals 4294967295. The audit system interprets -1, 4294967295, and "unset" in the same way. Satisfies: SRG-OS-000042-GPOS-00020, SRG-OS-000392-GPOS-00172, SRG-OS-000471-GPOS-00215
Check Content
Verify the operating system generates audit records when successful/unsuccessful attempts to use the "ssh-keysign" command occur. Check that the following system call is being audited by performing the following command to check the file system rules in "/etc/audit/audit.rules": $ sudo grep -w "/usr/libexec/openssh/ssh-keysign" /etc/audit/audit.rules -a always,exit -F path=/usr/libexec/openssh/ssh-keysign -F perm=x -F auid>=1000 -F auid!=unset -k privileged-ssh If the command does not return any output, this is a finding.
Fix Text
Configure the operating system to generate audit records when successful/unsuccessful attempts to use the "ssh-keysign" command occur. Add or update the following rule in "/etc/audit/rules.d/audit.rules": -a always,exit -F path=/usr/libexec/openssh/ssh-keysign -F perm=x -F auid>=1000 -F auid!=unset -k privileged-ssh The audit daemon must be restarted for the changes to take effect.
Additional Identifiers
Rule ID: SV-204556r861065_rule
Vulnerability ID: V-204556
Group Title: SRG-OS-000042-GPOS-00020
Expert Comments
CCIs
| Number | Definition |
|---|---|
| CCI-000135 |
The information system generates audit records containing the organization-defined additional, more detailed information that is to be included in the audit records. |
| CCI-000172 |
The information system generates audit records for the events defined in AU-2 d. with the content defined in AU-3. |
| CCI-002884 |
The organization audits nonlocal maintenance and diagnostic sessions^ organization-defined audit events. |