CVE-2026-68149

Description

In the Linux kernel, the following vulnerability has been resolved: fs: preserve ACL_DONT_CACHE state in forget_cached_acl() The ACL_DONT_CACHE state is meant to be a constant state for the inode for filesystems that want to opt out of posix acl caching. Commit facd61053cff1 ("fuse: fixes after adapting to new posix acl api") used this facility to opt out of posix acl caching for fuse inodes with fuse server that does not negotiate FUSE_POSIX_ACL (fc->posix_acl). The commit also takes care to gate the forget_all_cached_acls() call in fuse_set_acl() on fc->posix_acl because there is no need for it, but there are other placed in fuse code which call forget_all_cached_acls() unconditional to fc->posix_acl and those cause the loss of the ACL_DONT_CACHE state. This is not only a functional bug. Properly timed, a get_acl() from this fuse filesystem can return a stale cached value, as was observed in tests, because set_acl() does not invalidate the unintentional acl cache. We could fix this in fuse, but it actually makes no sense for the vfs helper forget_cached_acl() to invalidate the ACL_DONT_CACHE state, so let it not do that to fix fuse and future users of ACL_DONT_CACHE.

Gravité et risque d'exploitation

CVE-2026-68149 obtient un score CVSS de 8.4/10, soit une gravité élevée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.14 %, ce qui la place devant 2.7 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions <=6.12.*, 6.12.101, <4b9a5458d02e214ef2b384124ca626e3e381d778, 0, <ca03a7984a34f48085fd013e0d2cf4e6420b4acf, <=7.1.*, <b98fad81f1202b0eb26aacf3ff4cc7a21ed3b5bf, <834ddf899484a2f23129080e8773bc04f4691d07, <=6.6.*, 6.18.42, facd61053cff100973921d4d45d47cf53c747ec6, 7.1.6, <a019b074903b3ad0a9726087efd0e8291452023b, <=6.18.*, <6.2, <=*, 6.6.148, 7.2, 6.2) est présent sur votre parc.
• Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
• À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
• Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.

Références

• https://git.kernel.org/stable/c/b98fad81f1202b0eb26aacf3ff4cc7a21ed3b5bf
• https://git.kernel.org/stable/c/834ddf899484a2f23129080e8773bc04f4691d07
• https://git.kernel.org/stable/c/a019b074903b3ad0a9726087efd0e8291452023b
• https://git.kernel.org/stable/c/ca03a7984a34f48085fd013e0d2cf4e6420b4acf
• https://git.kernel.org/stable/c/4b9a5458d02e214ef2b384124ca626e3e381d778