STIGQter: STIG Summary: Tri-Lab Operating System Stack (TOSS) 5 Security Technical Implementation Guide Version: 1 Release: 1 Benchmark Date: 26 Mar 2026:

TOSS 5 must automatically lock an account when three unsuccessful login attempts occur during a 15-minute time period.

DISA Rule

SV-282361r1200063_rule

Vulnerability Number

V-282361

Group Title

SRG-OS-000021-GPOS-00005

Rule Version

TOSS-05-000305

Severity

CAT II

CCI(s)

• CCI-000044 - Enforce the organization-defined limit of consecutive invalid logon attempts by a user during the organization-defined time period.
• CCI-002238 - Automatically lock the account or node for either an organization-defined time period, until the locked account or node is released by an administrator, or delays the next logon prompt according to the organization-defined delay algorithm when the maximum number of unsuccessful logon attempts is exceeded.

Weight

10

Fix Recommendation

Configure TOSS 5 to lock out the "root" account after a number of incorrect login attempts within 15 minutes.

Enable "pam_faillock.so" using the following command:

$ authselect enable-feature with-faillock

Edit the "/etc/security/faillock.conf" file as follows:

fail_interval = 900

Check Contents

Note: If the system administrator (SA) demonstrates the use of an approved centralized account management method that locks an account after three unsuccessful login attempts within a period of 15 minutes, this requirement is not applicable.

Verify TOSS 5 locks an account after three unsuccessful login attempts within a period of 15 minutes using the following command:

$ grep fail_interval /etc/security/faillock.conf

fail_interval = 900

If the "fail_interval" option is not set to "900" or less (but not "0"), the line is commented out, or the line is missing, this is a finding.

Vulnerability Number

V-282361

Documentable

False

Rule Version

TOSS-05-000305

Severity Override Guidance

Note: If the system administrator (SA) demonstrates the use of an approved centralized account management method that locks an account after three unsuccessful login attempts within a period of 15 minutes, this requirement is not applicable.

Verify TOSS 5 locks an account after three unsuccessful login attempts within a period of 15 minutes using the following command:

$ grep fail_interval /etc/security/faillock.conf

fail_interval = 900

If the "fail_interval" option is not set to "900" or less (but not "0"), the line is commented out, or the line is missing, this is a finding.

Check Content Reference

M

Target Key

5738