CVE-2026-64031
Vulnérabilité élevée dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: erofs: fix managed cache race for unaligned extents After unaligned compressed extents were introduced, the following race could occur: [Thread 1] [Thread 2] (z_erofs_fill_bio_vec) <handle a Z_EROFS_PREALLOCATED_FOLIO folio> ... filemap_add_folio (1) (z_erofs_bind_cache) <the same folio is found..> .. .. folio_attach_private (2) filemap_add_folio (3) again Since (1) is executed but (2) hasn't been executed yet, it's possible that another thread finds the same managed folio in z_erofs_bind_cache() for a different pcluster and calls filemap_add_folio() again since folio->private is still Z_EROFS_PREALLOCATED_FOLIO. Fix this by explicitly clearing folio->private before making the folio visible in the managed cache so that another pcluster can simply wait on the locked managed folio as what we did for other shared cases [1]. This only impacts unaligned data compression (`-E48bit` with zstd, for example). [1] Commit 9e2f9d34dd12 ("erofs: handle overlapped pclusters out of crafted images properly") was originally introduced to handle crafted overlapped extents, but it addresses unaligned extents as well.
Gravité et risque d'exploitation
CVE-2026-64031 obtient un score CVSS de 7.8/10, soit une gravité élevée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.10 %, ce qui la place devant 0.8 % des CVE référencées.
Que faire ?
- Vérifiez si Linux (versions <=7.0.*, <649932fc3815eda2f24eb4de4b3a5e94886ee0b9, 6.18.34, <=*, <2718cdb6db0fdbe375e61f2980aada27bafb323e, 7.1, <6.15, 722f0fcdb0bb7d12a5c6d9460b9a7de1f735f36d, <=6.18.*, 7.0.11, <425d32d6288d7d845e486af9419bbedccd8c9103, 0, 6.15, <038166f873c4caf6e85cfd4ea0c5a5ba297b4e8b, 7361d1e3763baaf7b9349c576137851458ad38d1) 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.