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CVE-2026-53397

Vulnérabilité élevée dans Linux (Linux)

CVSS 7.5 · Élevée
EPSS 0.5%
Linux•Linux•Versions : <=6.1.*, <2.6.13, <=6.12.*, 6.6.144, 5.15.211, 0, a257cdd0e2179630d3201c32ba14d7fcb3c3a055, <=7.1.*, 2.6.13, <a5b42c1e4ff2befaa6b96f7cbf32174751eba083, 5.10.260, <=5.10.*, <=6.6.*, 6.12.95, <b94c4be77682aab06d65ca7296149e3bcfb37353, <136b416593f1349cf6f72c8e3d18f0f204ee8545, <1e96239fddcefacf6afe6c498357be68eacbcabc, <=6.18.*, 6.1.177, <0853ac544c590880d797b04daa33fcb72b6be0e1, 6.18.38, <887f92ceccf3eacd5f2402db21254d66372fae00, <=*, <=5.15.*, 7.1.3, <b2eb1ffd511d1b3c3e21122f97cbbccea411e277, <bd69a825485168ef74e815ecb286754b570fdcc7, 7.2

Description

In the Linux kernel, the following vulnerability has been resolved: nfsd: fix posix_acl leak on SETACL decode failure nfsaclsvc_decode_setaclargs() and nfs3svc_decode_setaclargs() each call nfs_stream_decode_acl() twice, first for NFS_ACL and then for NFS_DFACL. Each successful call transfers ownership of a freshly allocated posix_acl into argp->acl_access or argp->acl_default. If the first call succeeds but the second fails, the decoder returns false and argp->acl_access is left dangling. ACLPROC2_SETACL.pc_release was wired to nfssvc_release_attrstat and ACLPROC3_SETACL.pc_release was wired to nfs3svc_release_fhandle. Both only call fh_put() and have no knowledge of the ACL fields on argp. The posix_acl_release() pairs sat at the out: labels inside nfsacld_proc_setacl() and nfsd3_proc_setacl(), but svc_process() skips pc_func when pc_decode returns false, so that cleanup is unreachable on decode failure: svc_process_common() pc_decode() /* decode_setaclargs: false */ /* pc_func skipped */ pc_release() /* fh_put only -- ACLs leaked */ The orphaned posix_acl is leaked for the lifetime of the server. Fix by adding nfsaclsvc_release_setacl() and nfs3svc_release_setacl(), which release both argp->acl_access and argp->acl_default in addition to fh_put(), and wiring them as pc_release for their respective SETACL procedures. pc_release runs on every path svc_process() takes after decode, including decode failure, so the posix_acl_release() pairs are removed from the proc functions' out: labels to keep ownership in one place. This matches the existing release_getacl() pattern used by the sibling GETACL procedures.

Gravité et risque d'exploitation

CVE-2026-53397 obtient un score CVSS de 7.5/10, soit une gravité élevée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.53 %, ce qui la place devant 43.2 % des CVE référencées.

Que faire ?

  • Vérifiez si Linux (versions <=6.1.*, <2.6.13, <=6.12.*, 6.6.144, 5.15.211, 0, a257cdd0e2179630d3201c32ba14d7fcb3c3a055, <=7.1.*, 2.6.13, <a5b42c1e4ff2befaa6b96f7cbf32174751eba083, 5.10.260, <=5.10.*, <=6.6.*, 6.12.95, <b94c4be77682aab06d65ca7296149e3bcfb37353, <136b416593f1349cf6f72c8e3d18f0f204ee8545, <1e96239fddcefacf6afe6c498357be68eacbcabc, <=6.18.*, 6.1.177, <0853ac544c590880d797b04daa33fcb72b6be0e1, 6.18.38, <887f92ceccf3eacd5f2402db21254d66372fae00, <=*, <=5.15.*, 7.1.3, <b2eb1ffd511d1b3c3e21122f97cbbccea411e277, <bd69a825485168ef74e815ecb286754b570fdcc7, 7.2) 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

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