CVE-2026-53396Network attack vector

Authenticated service interruption via leaked ACL allocations

Published Jul 19, 2026 · Updated Jul 19, 2026

Resource leak in Linux Kernel 6.19 through 7.1.2 allows remote authenticated users to exhaust memory with crafted NFSv4 OPEN requests. In nfsd4_create_file(), a failing start_creating() path bypasses nfsd_attrs_free(), leaving populated POSIX ACL allocations unreleased; the routine also discards nfsd4_acl_to_attr() errors and creates files without requested ACLs. Access requires an authenticated NFS client with create permission on an exported directory; repeated overlong filenames consume kernel memory, while unsupported ACE types cause ACL-free file creation.

CVSS severity7.1
High
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Resource leak in Linux Kernel 6.19 through 7.1.2 allows remote authenticated users to exhaust memory with crafted NFSv4 OPEN requests. In nfsd4_create_file(), a failing start_creating() path bypasses nfsd_attrs_free(), leaving populated POSIX ACL allocations unreleased; the routine also discards nfsd4_acl_to_attr() errors and creates files without requested ACLs. Access requires an authenticated NFS client with create permission on an exported directory; repeated overlong filenames consume kernel memory, while unsupported ACE types cause ACL-free file creation.

The record

CVE
CVE-2026-53396
Published
Jul 19, 2026
Updated
Jul 19, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-401, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 19, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=6.19
  2. Affected versionversion=7ab96df840e60eb933abfe65fc5fe44e72f16dc0 <18cf006a08babec0bbac2a3784f8f28e56e47490
  3. Affected versionversion=7ab96df840e60eb933abfe65fc5fe44e72f16dc0 <24c975bbdd564d7d0ad90294bfa69729830345de

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=6.19; version=7ab96df840e60eb933abfe65fc5fe44e72f16dc0 <18cf006a08babec0bbac2a3784f8f28e56e47490; version=7ab96df840e60eb933abfe65fc5fe44e72f16dc0 <24c975bbdd564d7d0ad90294bfa69729830345de

Published CVSS scores

7.1kernel.orgCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-401Missing Release of Memory after Effective Lifetime
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo