CVE-2026-64059

Local denial of service via folio reference leaks

Published Jul 19, 2026 · Updated Jul 19, 2026

Reference-count leaks in Linux Kernel netfs write handling allow local users to exhaust kernel memory through repeated filesystem writes. The netfs_perform_write() path mishandles folio->private transitions among cache markers, group pointers, and netfs_folio objects, permitting duplicate private-data attachments without releasing associated references. Exploitation requires local write access to a netfs-backed filesystem; sustained writes consume memory and can interrupt service without changing or disclosing data.

CVSS severityUnavailable
Unscored
EPSS probability0.12%
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

Reference-count leaks in Linux Kernel netfs write handling allow local users to exhaust kernel memory through repeated filesystem writes. The netfs_perform_write() path mishandles folio->private transitions among cache markers, group pointers, and netfs_folio objects, permitting duplicate private-data attachments without releasing associated references. Exploitation requires local write access to a netfs-backed filesystem; sustained writes consume memory and can interrupt service without changing or disclosing data.

The record

CVE
CVE-2026-64059
Published
Jul 19, 2026
Updated
Jul 19, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-911, T1499.001
Attack vector
local
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=6.12
  2. Affected versionversion=8f52de0077ba3bf41e5d53d67a185700f41efce7 <0969ea8370bad0e4fb6131b6a7bed9e7ec522ac7
  3. Affected versionversion=8f52de0077ba3bf41e5d53d67a185700f41efce7 <551b5c71ee312ca7646ddb605231c1016e8cbb18
  4. Affected versionversion=8f52de0077ba3bf41e5d53d67a185700f41efce7 <7f040243c74d72b45b22246c7d9e621fbeab44ac
  5. Affected versionversion=8f52de0077ba3bf41e5d53d67a185700f41efce7 <ccde2ac757c713535b224233a296de40efe5212d

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=6.12; version=8f52de0077ba3bf41e5d53d67a185700f41efce7 <0969ea8370bad0e4fb6131b6a7bed9e7ec522ac7; version=8f52de0077ba3bf41e5d53d67a185700f41efce7 <551b5c71ee312ca7646ddb605231c1016e8cbb18; version=8f52de0077ba3bf41e5d53d67a185700f41efce7 <7f040243c74d72b45b22246c7d9e621fbeab44ac; version=8f52de0077ba3bf41e5d53d67a185700f41efce7 <ccde2ac757c713535b224233a296de40efe5212d

Published CVSS scores

No CVSS assessment is available in this record.

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)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-911Improper Update of Reference Count
T1499.001OS Exhaustion Flood

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