| name | CIS Ubuntu 14.04 LTS - 1.5.1 Ensure core dumps are restricted |
| description | Verify that core dumps are restricted to prevent information disclosure from memory dumps |
| category | cis-os-hardening |
| version | 2.1.0 |
| author | cyberstrike-official |
| tags | ["cis","ubuntu","ubuntu-14.04","level-1","scored","hardening"] |
| cis_id | 1.5.1 |
| cis_benchmark | CIS Ubuntu Linux 14.04 LTS Benchmark v2.1.0 |
| tech_stack | ["ubuntu","linux"] |
| cwe_ids | [] |
| chains_with | [] |
| prerequisites | [] |
| severity_boost | medium |
1.5.1 Ensure core dumps are restricted (Scored)
Profile Applicability
- Level 1 - Server
- Level 1 - Workstation
Description
A core dump is the memory of an executable program. It is generally used to determine why a program aborted. It can also be used to glean confidential information from a core file. The system provides the ability to set a soft limit for core dumps, but this can be overridden by the user.
Rationale
Setting a hard limit on core dumps prevents users from overriding the soft variable. If core dumps are required, consider setting limits for user groups (see limits.conf(5)). In addition, setting the fs.suid_dumpable variable to 0 will prevent setuid programs from dumping core.
Audit Procedure
Run the following commands and verify output matches:
grep "hard core" /etc/security/limits.conf /etc/security/limits.d/*
sysctl fs.suid_dumpable
grep "fs\.suid_dumpable" /etc/sysctl.conf /etc/sysctl.d/*
Expected Result
* hard core 0
fs.suid_dumpable = 0
fs.suid_dumpable = 0
Remediation
Add the following line to /etc/security/limits.conf or a /etc/security/limits.d/* file:
* hard core 0
Set the following parameter in /etc/sysctl.conf or a /etc/sysctl.d/* file:
fs.suid_dumpable = 0
Run the following command to set the active kernel parameter:
sysctl -w fs.suid_dumpable=0
Default Value
Not applicable.
Notes
It has been reported that due to Ubuntu bug #50093 this setting (and some others) can fail to apply properly on reboot requiring it to be manually re-applied. One method of accomplishing this is to add sysctl -p to run on reboot to your systems crontab.
References
- CIS Controls: 13 Data Protection
Profile
- Level 1 - Server
- Level 1 - Workstation