CVE-2026-89701Network attack vectorHinoki check available

Malformed timestamps via unchecked nanosecond values

Published Sep 11, 2026 · Updated Sep 11, 2026

Improper input validation in Linux 6.14 NFSD allows remote attackers to write malformed timestamps to disk through NFSv4. The TIME_DELEG_ACCESS and TIME_DELEG_MODIFY decode arms in nfs4xdr.c and nfs4callback.c copy an unchecked uint32_t into tv_nsec instead of rejecting values at or above NSEC_PER_SEC. Reachability requires an active NFSD path processing those attributes, and the bounded consequence is invalid file timestamp metadata reaching the backing filesystem.

CVSS severityUnavailable
Unscored
EPSS probability0.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Improper input validation in Linux 6.14 NFSD allows remote attackers to write malformed timestamps to disk through NFSv4. The TIME_DELEG_ACCESS and TIME_DELEG_MODIFY decode arms in nfs4xdr.c and nfs4callback.c copy an unchecked uint32_t into tv_nsec instead of rejecting values at or above NSEC_PER_SEC. Reachability requires an active NFSD path processing those attributes, and the bounded consequence is invalid file timestamp metadata reaching the backing filesystem.

The record

CVE
CVE-2026-89701
Published
Sep 11, 2026
Updated
Sep 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
network
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 11, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 11, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=6.14
  2. Affected versionversion=6ae30d6eb26bce02c48c60074b4306270e2434c1 <0f4a767340fad392bd656115b8752005518c9065
  3. Affected versionversion=6ae30d6eb26bce02c48c60074b4306270e2434c1 <5eb489831a9fd4754f4baf26e6989efb66ce104c
  4. Affected versionversion=6ae30d6eb26bce02c48c60074b4306270e2434c1 <7e7b93da7fa2e77f977096251899d1410986adf6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=6.14; version=6ae30d6eb26bce02c48c60074b4306270e2434c1 <0f4a767340fad392bd656115b8752005518c9065; version=6ae30d6eb26bce02c48c60074b4306270e2434c1 <5eb489831a9fd4754f4baf26e6989efb66ce104c; version=6ae30d6eb26bce02c48c60074b4306270e2434c1 <7e7b93da7fa2e77f977096251899d1410986adf6

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

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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