crun is an open source OCI Container Runtime fully written in C. Prior to version 1.28, crun's default device setup opens the container rootfs `/dev` directory without `O_NOFOLLOW`. If an OCI bundle contains `rootfs/dev` as a symlink and the bundle configuration does not mount `/dev`, crun follows that symlink and creates the default device nodes and stdio symlinks at the symlink target outside the container rootfs. In a local rootful crun replay, this created fixed device nodes and symlinks outside the rootfs before crun returned failure. A pre-existing file named `ptmx` in the target directory was also replaced by crun's forced `ptmx -> pts/ptmx` symlink. Version 1.28 fixes the issue.
| Métrique | Valeur | Interprétation |
|---|---|---|
|
AV (Vecteur d'Attaque)
Attack Vector
|
Local (L)
|
Exploit nécessite un accès local au système |
|
AC (Complexité d'Attaque)
Attack Complexity
|
Low (L)
|
Peu de conditions requises pour exploiter |
|
PR (Privilèges Requis)
Privileges Required
|
None (N)
|
Aucune authentification requise |
|
UI (Interaction Utilisateur)
User Interaction
|
None (N)
|
Aucune interaction utilisateur nécessaire |
|
S (Périmètre)
Scope
|
Unchanged (U)
|
Impact reste dans le périmètre du composant compromis |
|
C (Impact Confidentialité)
Confidentiality Impact
|
None (N)
|
Aucune divulgation d'informations |
|
I (Impact Intégrité)
Integrity Impact
|
Low (L)
|
Modification limitée des données possible |
|
A (Impact Disponibilité)
Availability Impact
|
None (N)
|
Aucune interruption de service |
crun follows rootfs /dev symlink while creating default devices