# yaml-language-server: $schema=../../../../schema/control.schema.json
id: CB-DEB-BOOT-010
title: Keep no AppArmor profile in complain mode
finding:
  title: Some AppArmor profiles only log violations instead of blocking them
  description: A profile in complain mode confines nothing; the program it covers runs as if it had no profile.
status: active
profiles: [server-hardened, desktop-hardened]
risk:
  severity: medium
assessment: automated
tags: [apparmor, mac]

description: |
  Each loaded AppArmor profile runs in a mode. In `enforce` mode, accesses outside the profile
  are blocked and logged. In `complain` mode, they are only logged. Profiles flagged `unconfined`
  are a third case: they do not restrict the program but attach specific rights to it (Debian 13
  ships many of them for user namespace mediation), and are out of scope here.
rationale: |
  Complain mode is meant for writing and testing profiles. A profile left in complain mode in
  production gives a false sense of confinement: the program is not restricted at all.
impact: |
  Switching a profile to enforce mode can break the program it covers if the profile is
  incomplete. Debian 13 ships several profiles in complain mode on purpose; enforce them one by
  one, checking the logs (`journalctl -k | grep apparmor`) for denials.

audit:
  manual: |
    Run `aa-status --complaining`. It must print `0`.
    `aa-status` lists the profiles in complain mode by name.
  checks:
    - id: complain-count
      engine: shell
      description: Number of loaded profiles in complain mode.
      spec:
        script: |
          n=$(aa-status --complaining 2>/dev/null) || exit 3
          echo "$n"
          [ "$n" -eq 0 ]

remediation:
  manual: |
    1. List the profiles in complain mode: `aa-status`.
    2. For each one, install `apparmor-utils` and run `aa-enforce /etc/apparmor.d/<profile>`.
    3. Watch for denials with `journalctl -k | grep apparmor` and fix or revert the profile.
  rollback: |
    Put a profile back in complain mode with `aa-complain /etc/apparmor.d/<profile>`.

references:
  - title: aa-status(8), Debian manual pages
    url: https://manpages.debian.org/trixie/apparmor/aa-status.8.en.html
    publisher: Debian
    kind: vendor-doc
    accessed: 2026-10-18
  - title: Debian Wiki - AppArmor/HowToUse
    url: https://wiki.debian.org/AppArmor/HowToUse
    publisher: Debian
    kind: vendor-doc
    accessed: 2026-10-18
  - title: ANSSI-BP-028 v2.0 - Recommandations de configuration d'un système GNU/Linux (R45)
    url: https://messervices.cyber.gouv.fr/documents-guides/fr_np_linux_configuration-v2.0.pdf
    publisher: ANSSI
    kind: guide
    accessed: 2026-10-18
mappings:
  - framework: anssi-linux
    framework_version: "2.0"
    id: R45
    relation: partial
    note: R45 also asks for AppArmor to be enabled, which is CB-DEB-BOOT-008.
  - framework: nist-800-53r5
    framework_version: "5.1.1"
    id: AC-3
    relation: related
  - framework: cis-debian-12
    framework_version: "2.0.0"
    id: "1.3.1.3"
    relation: equivalent
  - framework: cis-debian-13
    framework_version: "1.1.0"
    id: "1.3.1.3"
    relation: equivalent
threats:
  - framework: mitre-attack
    id: T1068
related_controls:
  - id: CB-DEB-BOOT-008
    type: requires

authors:
  - name: Alice
    github: Sn0wAlice
verified:
  - date: 2026-10-18
    by: Sn0wAlice
    versions: ["12"]
    environment: Proxmox VM, Debian 12 genericcloud image, kernel 6.1.0-54-cloud-amd64, BIOS boot
    notes: Passes on a fresh install (11 profiles, all enforce).
  - date: 2026-10-18
    by: Sn0wAlice
    versions: ["13"]
    environment: Proxmox VM, Debian 13 genericcloud image, kernel 6.12.113+deb13-cloud-amd64, BIOS boot
    notes: Fails on a fresh install (23 complain profiles); manual procedure with aa-enforce makes it pass.
introduced_in: 0.1.0
created: 2026-10-18
updated: 2026-10-18