CVE-2026-53397

/// Technical 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_set

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References