# CVE-2026-53396: linux: In the Linux kernel, the following vulnerability has been resolved:  nfsd: fix posix_acl leak and ignored error in nf...

CVE-2026-53396 is fixed in linux on 1 platform by DEBIAN-CVE-2026-53396 (version 7.1.3-1), released July 20, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-53396
- Priority: High
- CVSS: 7.1 (high)
- EPSS: 0.0038
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jul 19, 2026

## Description

In the Linux kernel, the following vulnerability has been resolved:  nfsd: fix posix_acl leak and ignored error in nfsd4_create_file  nfsd4_create_file() has two bugs in its ACL handling:  The return value of nfsd4_acl_to_attr() is silently discarded.  When the NFSv4-to-POSIX ACL conversion fails (e.g., -EINVAL for unsupported ACE types), the file is created without any ACL and the client receives NFS4_OK.  This violates RFC 7530/8881 which require the server to reject unsupported attributes on CREATE.  When start_creating() fails after ACL attributes have been populated in attrs (either via nfsd4_acl_to_attr or via ownership transfer from open->op_dpacl/op_pacl), the function jumps to out_write which skips nfsd_attrs_free().  The posix_acl allocations are leaked.  A client can trigger this repeatedly with OPEN(CREATE), ACL attributes, and an invalid filename (e.g., longer than NAME_MAX).  Fix both by capturing the nfsd4_acl_to_attr() return value and by changing the early error paths to jump to out instead of out_write. Initialize child to ERR_PTR(-EINVAL) so that end_creating() is safe to call even if start_creating() was never reached.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 14 | 7.1.3-1 | [DEBIAN-CVE-2026-53396](https://patchblox.com/security/data/fix/linux/debian-cve-2026-53396.md) | Jul 20, 2026 |

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Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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