Detections
Analytics

4.1.12 Ensure unsuccessful unauthorized file access attempts are collected - EPERM 32 bit

Information

Monitor for unsuccessful attempts to access files. The parameters below are associated with system calls that control creation ( creat ), opening ( open , openat ) and truncation ( truncate , ftruncate ) of files. An audit log record will only be written if the user is a non-privileged user (auid > = 500), is not a Daemon event (auid=4294967295) and if the system call returned EACCES (permission denied to the file) or EPERM (some other permanent error associated with the specific system call). All audit records will be tagged with the identifier 'access.'

Rationale:

Failed attempts to open, create or truncate files could be an indication that an individual or process is trying to gain unauthorized access to the system.

Solution

For 32 bit systems Edit or create a file in the /etc/audit/rules.d/ directory ending in .rules
Example: vi /etc/audit/rules.d/audit.rules
and add the following lines:

-a always,exit -F arch=b32 -S creat -S open -S openat -S truncate -S ftruncate -F exit=-EACCES -F auid>=500 -F auid!=4294967295 -k access
-a always,exit -F arch=b32 -S creat -S open -S openat -S truncate -S ftruncate -F exit=-EPERM -F auid>=500 -F auid!=4294967295 -k access

For 64 bit systems Edit or create a file in the /etc/audit/rules.d/ directory ending in .rules
Example: vi /etc/audit/rules.d/audit.rules
and add the following lines:

-a always,exit -F arch=b64 -S creat -S open -S openat -S truncate -S ftruncate -F exit=-EACCES -F auid>=500 -F auid!=4294967295 -k access
-a always,exit -F arch=b32 -S creat -S open -S openat -S truncate -S ftruncate -F exit=-EACCES -F auid>=500 -F auid!=4294967295 -k access
-a always,exit -F arch=b64 -S creat -S open -S openat -S truncate -S ftruncate -F exit=-EPERM -F auid>=500 -F auid!=4294967295 -k access
-a always,exit -F arch=b32 -S creat -S open -S openat -S truncate -S ftruncate -F exit=-EPERM -F auid>=500 -F auid!=4294967295 -k access

Notes:

Reloading the auditd config to set active settings may require a system reboot.

This Benchmark recommendation maps to:

Red Hat Enterprise Linux 7 Security Technical Implementation Guide:

Version 2, Release: 3 Benchmark Date: 26 Apr 2019



Vul ID: V-72123

Rule ID: SV-86747r4_rule

STIG ID: RHEL-07-030500

Severity: CAT II



Vul ID: V-72125

Rule ID: SV-86749r4_rule

STIG ID: RHEL-07-030510

Severity: CAT II



Vul ID: V-72127

Rule ID: SV-86751r4_rule

STIG ID: RHEL-07-030520

Severity: CAT II



Vul ID: V-72129

Rule ID: SV-86753r4_rule

STIG ID: RHEL-07-030530

Severity: CAT II



Vul ID: V-72131

Rule ID: SV-86755r4_rule

STIG ID: RHEL-07-030540

Severity: CAT II



Vul ID: V-72133

Rule ID: SV-86757r4_rule

STIG ID: RHEL-07-030550

Severity: CAT II

See Also

https://workbench.cisecurity.org/files/2688

Item Details

Category: AUDIT AND ACCOUNTABILITY

References: 800-53|AU-3, CSCv7|14.9

Plugin: Unix

Control ID: 1e358a4437c0c2d4438865597952d52e575ac23d202490ced64c56b3eed2cca5