CVE-2026-89674Network attack vector

Kernel memory disclosure or corruption via XDR miscalculation

Published Sep 11, 2026 · Updated Sep 11, 2026

Memory corruption in the Linux nfsd server allows remote attackers to disclose kernel memory or overwrite an XDR buffer through NFSv4 LAYOUTGET. nfsd4_ff_encode_layoutget() reserves the wrong length by omitting fields and miscalculating padding for file handles, user IDs, and group IDs. Exposure requires access to a suitable NFSv4 export; affected replies can write five bytes past the reservation or return stale kernel-buffer contents.

CVSS severityUnavailable
Unscored
EPSS probability0.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory corruption in the Linux nfsd server allows remote attackers to disclose kernel memory or overwrite an XDR buffer through NFSv4 LAYOUTGET. nfsd4_ff_encode_layoutget() reserves the wrong length by omitting fields and miscalculating padding for file handles, user IDs, and group IDs. Exposure requires access to a suitable NFSv4 export; affected replies can write five bytes past the reservation or return stale kernel-buffer contents.

The record

CVE
CVE-2026-89674
Published
Sep 11, 2026
Updated
Sep 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1190
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=4.8
  2. Affected versionversion=9b9960a0ca4773e21c4b153ed355583946346b25 <0380129b1373c437eb35401a174671c8888f4b80
  3. Affected versionversion=9b9960a0ca4773e21c4b153ed355583946346b25 <c81cef6a805dec266c10fc4f83c93d6fcf1a2b43
  4. Affected versionversion=9b9960a0ca4773e21c4b153ed355583946346b25 <e7d9d23ecd9172f05b09bb678ff22db8e361c428
  5. Affected versionversion=9b9960a0ca4773e21c4b153ed355583946346b25 <f9868174af49d207fbaf0c5e055d088a983684af

What conditions does exploitation require?

Attack vectornetwork
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=4.8; version=9b9960a0ca4773e21c4b153ed355583946346b25 <0380129b1373c437eb35401a174671c8888f4b80; version=9b9960a0ca4773e21c4b153ed355583946346b25 <c81cef6a805dec266c10fc4f83c93d6fcf1a2b43; version=9b9960a0ca4773e21c4b153ed355583946346b25 <e7d9d23ecd9172f05b09bb678ff22db8e361c428; version=9b9960a0ca4773e21c4b153ed355583946346b25 <f9868174af49d207fbaf0c5e055d088a983684af

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)
Vectornetwork
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1190Exploit Public-Facing Application

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

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Your stack

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