modules:
  - module: github.com/containers/buildah
    versions:
      - fixed: 1.27.1
    vulnerable_at: 1.27.0
    packages:
      - package: github.com/containers/buildah
        symbols:
          - Builder.configureUIDGID
        derived_symbols:
          - Builder.Run
description: |
    SGID programs executed in a container can access files that have negative
    group permissions for the user's primary group.

    Consider a file which is owned by user u1 and group g1, permits user and
    other read access, and does NOT permit group read access. This file is
    readable by u1 and all other users except for ones in group g1.

    A program with the set-group-ID (SGID) bit set assumes the primary group
    of the program's group when it executes.

    A user with the primary group g1 who executes an SGID program owned by
    group g2 should not be able to access the file described above. While
    the program executes with the primary group g2, the group g1 should
    remain in its supplementary groups, blocking access to the file.

    Buildah does not correctly add g1 to the supplementary groups in this
    scenario, permitting unauthorized access.
cves:
  - CVE-2022-2990
ghsas:
  - GHSA-fjm8-m7m6-2fjp
references:
  - article: https://www.benthamsgaze.org/2022/08/22/vulnerability-in-linux-containers-investigation-and-mitigation/
  - fix: https://github.com/containers/buildah/commit/4a8bf740e862f2438279c6feee2ea59ddf0cda0b