CVE-2026-90237Hinoki check available

Local privilege escalation via stale expectation links

Published Sep 17, 2026 · Updated Sep 18, 2026

Memory corruption in Linux kernel netfilter nft_ct from 5.3 through 7.2.5 allows local users to gain kernel privileges via custom expectations. The nft_ct expectation path inserts an expectation before conntrack extension reallocation, leaving its .pprev link attached to the wrong hlist_head and enabling stale-list memory corruption. Exploitation requires local low-privileged access and custom connection-tracking expectation processing; successful abuse compromises kernel confidentiality, integrity, and availability.

CVSS severity7.8
High
EPSS probability0.17%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Memory corruption in Linux kernel netfilter nft_ct from 5.3 through 7.2.5 allows local users to gain kernel privileges via custom expectations. The nft_ct expectation path inserts an expectation before conntrack extension reallocation, leaving its .pprev link attached to the wrong hlist_head and enabling stale-list memory corruption. Exploitation requires local low-privileged access and custom connection-tracking expectation processing; successful abuse compromises kernel confidentiality, integrity, and availability.

The record

CVE
CVE-2026-90237
Published
Sep 17, 2026
Updated
Sep 18, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 17, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 18, 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=5.3
  2. Affected versionversion=857b46027d6f91150797295752581b7155b9d0e1 <3679da4ad8be84cddaf40bc307fef1fe13e051ff
  3. Affected versionversion=857b46027d6f91150797295752581b7155b9d0e1 <af3fe52fd108fd38235e4813df62442ed0f1d8ff

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.3; version=857b46027d6f91150797295752581b7155b9d0e1 <3679da4ad8be84cddaf40bc307fef1fe13e051ff; version=857b46027d6f91150797295752581b7155b9d0e1 <af3fe52fd108fd38235e4813df62442ed0f1d8ff

Published CVSS scores

7.8LinuxCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1068Exploitation for Privilege Escalation

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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