---
title: Disable Core Dumps for SUID programs
description: Datadog, the leading service for cloud-scale monitoring.
breadcrumbs: Docs > Datadog Security > OOTB Rules > Disable Core Dumps for SUID programs
---

> For the complete documentation index, see [llms.txt](https://docs.datadoghq.com/llms.txt).

# Disable Core Dumps for SUID programs
 
## Description{% #description %}

To set the runtime status of the `fs.suid_dumpable` kernel parameter, run the following command:

```
$ sudo sysctl -w fs.suid_dumpable=0
```

To make sure that the setting is persistent, add the following line to a file in the directory `/etc/sysctl.d`:

```
fs.suid_dumpable = 0
```

## Rationale{% #rationale %}

The core dump of a setuid program is more likely to contain sensitive data, as the program itself runs with greater privileges than the user who initiated execution of the program. Disabling the ability for any setuid program to write a core file decreases the risk of unauthorized access of such data.

## Remediation{% #remediation %}

### Shell script{% #shell-script %}

The following script can be run on the host to remediate the issue.

```bash
#!/bin/bash

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}' 'linux-base' 2>/dev/null | grep -q '^installed$'; then

#
# Set sysctl config file which to save the desired value
#

SYSCONFIG_FILE="/etc/sysctl.conf"


# Comment out any occurrences of fs.suid_dumpable from /etc/sysctl.d/*.conf files

for f in /etc/sysctl.d/*.conf /run/sysctl.d/*.conf /usr/local/lib/sysctl.d/*.conf /etc/ufw/sysctl.conf; do


  # skip systemd-sysctl symlink (/etc/sysctl.d/99-sysctl.conf -> /etc/sysctl.conf)
  if [[ "$(readlink -f "$f")" == "/etc/sysctl.conf" ]]; then continue; fi

  if [[ "$(readlink -f "$f")" == "$(readlink -f "${SYSCONFIG_FILE}")" ]]; then
    # entries starting with fs.suid_dumpable in the file this remediation writes to
    # are replaced in place below, commenting them out would make the remediation non-idempotent
    matching_list=$(grep -P '^(?!#)(?!fs.suid_dumpable\b).*[\s]*fs.suid_dumpable.*$' $f | uniq )
  else
    matching_list=$(grep -P '^(?!#).*[\s]*fs.suid_dumpable.*$' $f | uniq )
  fi
  if ! test -z "$matching_list"; then
    while IFS= read -r entry; do
      escaped_entry=$(sed -e 's|/|\\/|g' <<< "$entry")
      # comment out "fs.suid_dumpable" matches to preserve user data
      sed -i --follow-symlinks "s/^${escaped_entry}$/# &/g" $f
    done <<< "$matching_list"
  fi
done

#
# Set runtime for fs.suid_dumpable
#
if ! /bin/false ; then
    /sbin/sysctl -q -n -w fs.suid_dumpable="0"
fi

#
# If fs.suid_dumpable present in /etc/sysctl.conf, change value to "0"
#	else, add "fs.suid_dumpable = 0" to /etc/sysctl.conf
#

# Strip any search characters in the key arg so that the key can be replaced without
# adding any search characters to the config file.
stripped_key=$(sed 's/[\^=\$,;+]*//g' <<< "^fs.suid_dumpable")

# shellcheck disable=SC2059
printf -v formatted_output "%s = %s" "$stripped_key" "0"

# If the key exists, change it. Otherwise, add it to the config_file.
# We search for the key string followed by a word boundary (matched by \>),
# so if we search for 'setting', 'setting2' won't match.
if LC_ALL=C grep -q -m 1 -i -e "^fs.suid_dumpable\\>" "${SYSCONFIG_FILE}"; then
    escaped_formatted_output=$(sed -e 's|/|\\/|g' <<< "$formatted_output")
    LC_ALL=C sed -i --follow-symlinks "s/^fs.suid_dumpable\\>.*/$escaped_formatted_output/gi" "${SYSCONFIG_FILE}"
else
    if [[ -s "${SYSCONFIG_FILE}" ]] && [[ -n "$(tail -c 1 -- "${SYSCONFIG_FILE}" || true)" ]]; then
        LC_ALL=C sed -i --follow-symlinks '$a'\\ "${SYSCONFIG_FILE}"
    fi
    printf '%s\n' "$formatted_output" >> "${SYSCONFIG_FILE}"
fi

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi
```

### Ansible playbook{% #ansible-playbook %}

The following playbook can be run with Ansible to remediate the issue.

```gdscript3
- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - PCI-DSSv4-3.3
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_fs_suid_dumpable

- name: Disable Core Dumps for SUID programs - Set fact for sysctl paths
  ansible.builtin.set_fact:
    sysctl_paths:
    - /etc/sysctl.d/
    - /run/sysctl.d/
    - /usr/local/lib/sysctl.d/
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - PCI-DSSv4-3.3
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_fs_suid_dumpable

- name: Disable Core Dumps for SUID programs - Find all files that contain fs.suid_dumpable
  ansible.builtin.shell:
    cmd: |-
      set -o pipefail
      find -L {{ sysctl_paths | join(" ") }} -type f -name '*.conf' | xargs grep -HP '^\s*fs.suid_dumpable\s*=\s*.*$'
    executable: /bin/bash
  register: find_all_values
  check_mode: false
  changed_when: false
  failed_when: false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - PCI-DSSv4-3.3
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_fs_suid_dumpable

- name: Disable Core Dumps for SUID programs - Find all files that set fs.suid_dumpable
    to correct value
  ansible.builtin.shell:
    cmd: |-
      set -o pipefail
      find -L {{ sysctl_paths | join(" ") }} -type f -name '*.conf' | xargs grep -HP '^\s*fs.suid_dumpable\s*=\s*0$'
    executable: /bin/bash
  register: find_correct_value
  check_mode: false
  changed_when: false
  failed_when: false
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - PCI-DSSv4-3.3
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_fs_suid_dumpable

- name: Disable Core Dumps for SUID programs - Comment out any occurrences of fs.suid_dumpable
    from config files
  ansible.builtin.replace:
    path: '{{ item | split(":") | first }}'
    regexp: ^[\s]*fs.suid_dumpable
    replace: '#fs.suid_dumpable'
  loop: '{{ find_all_values.stdout_lines }}'
  when:
  - '"linux-base" in ansible_facts.packages'
  - find_correct_value.stdout_lines | length == 0 or find_all_values.stdout_lines
    | length > find_correct_value.stdout_lines | length
  tags:
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - PCI-DSSv4-3.3
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_fs_suid_dumpable

- name: Disable Core Dumps for SUID programs - Comment out any occurrences of fs.suid_dumpable
    from /etc/ufw/sysctl.conf
  ansible.builtin.replace:
    path: /etc/ufw/sysctl.conf
    regexp: (^[\s]*fs.suid_dumpable.*$)
    replace: '# \1'
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - PCI-DSSv4-3.3
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_fs_suid_dumpable

- name: Disable Core Dumps for SUID programs - Ensure sysctl fs.suid_dumpable is set
    to 0
  ansible.posix.sysctl:
    name: fs.suid_dumpable
    value: '0'
    sysctl_file: /etc/sysctl.conf
    state: present
    reload: true
  when: '"linux-base" in ansible_facts.packages'
  tags:
  - NIST-800-53-SI-11(a)
  - NIST-800-53-SI-11(b)
  - PCI-DSSv4-3.3
  - PCI-DSSv4-3.3.1
  - PCI-DSSv4-3.3.1.1
  - disable_strategy
  - low_complexity
  - medium_disruption
  - medium_severity
  - reboot_required
  - sysctl_fs_suid_dumpable
```