CVE-2026-98537Hinoki check available

Kernel fault via unchecked workqueue current_pwq dereference

Published Oct 18, 2026 · Updated Oct 18, 2026

NULL dereference in Linux workqueue handling allows attackers to trigger a kernel fault via an out-of-memory flush path. In kernel/workqueue.c, check_flush_dependency() treats worker identity as proof of active work and dereferences current_pwq even when it is NULL. The reported path involves an out-of-memory notifier during worker creation; attacker control and required privileges are not established.

CVSS severityUnavailable
Unscored
EPSS probability0.22%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

NULL dereference in Linux workqueue handling allows attackers to trigger a kernel fault via an out-of-memory flush path. In kernel/workqueue.c, check_flush_dependency() treats worker identity as proof of active work and dereferences current_pwq even when it is NULL. The reported path involves an out-of-memory notifier during worker creation; attacker control and required privileges are not established.

The record

CVE
CVE-2026-98537
Published
Oct 18, 2026
Updated
Oct 18, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Oct 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 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=4.5
  2. Affected versionversion=fca839c00a12d682cb59b3b620d109a1d850b262 <0c6b9b1e295aeff1132ac7aa738148cc65f06485
  3. Affected versionversion=fca839c00a12d682cb59b3b620d109a1d850b262 <1dccf5dc2f8fe688270b261ca4216e03c6a1e674
  4. Affected versionversion=fca839c00a12d682cb59b3b620d109a1d850b262 <513121e69388604619ea8c0ee07e86a3d1b5b5dc
  5. Affected versionversion=fca839c00a12d682cb59b3b620d109a1d850b262 <8ffececcb88262389b4f91fed0fe4884b68204bc
  6. Affected versionversion=fca839c00a12d682cb59b3b620d109a1d850b262 <9bb739a5c5a570c28a62afb98e9326e2a49743c1
  7. Affected versionversion=fca839c00a12d682cb59b3b620d109a1d850b262 <cc190a6a1d20b87e6a9435202fc2a3bd84c79fb3
  8. Affected versionversion=fca839c00a12d682cb59b3b620d109a1d850b262 <db6365ced4d5855e321f772b240c0e473bcfcdd5
  9. Affected versionversion=fca839c00a12d682cb59b3b620d109a1d850b262 <f97e6d0572d1b39998e053732332bc3cfdd0b9aa

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=4.5; version=fca839c00a12d682cb59b3b620d109a1d850b262 <0c6b9b1e295aeff1132ac7aa738148cc65f06485; version=fca839c00a12d682cb59b3b620d109a1d850b262 <1dccf5dc2f8fe688270b261ca4216e03c6a1e674; version=fca839c00a12d682cb59b3b620d109a1d850b262 <513121e69388604619ea8c0ee07e86a3d1b5b5dc; version=fca839c00a12d682cb59b3b620d109a1d850b262 <8ffececcb88262389b4f91fed0fe4884b68204bc; version=fca839c00a12d682cb59b3b620d109a1d850b262 <9bb739a5c5a570c28a62afb98e9326e2a49743c1; version=fca839c00a12d682cb59b3b620d109a1d850b262 <cc190a6a1d20b87e6a9435202fc2a3bd84c79fb3; version=fca839c00a12d682cb59b3b620d109a1d850b262 <db6365ced4d5855e321f772b240c0e473bcfcdd5; version=fca839c00a12d682cb59b3b620d109a1d850b262 <f97e6d0572d1b39998e053732332bc3cfdd0b9aa

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.

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)
VectorUnavailable
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.

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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