CVE-2026-98260

Kernel use-after-free via stale POSIX timer queue

Published Oct 6, 2026 · Updated Oct 6, 2026

Use-after-free in Linux kernel POSIX CPU timers allows local users to trigger kernel memory corruption when a non-leader thread's exec fails. After de_thread changes PID ownership, timer deletion mistakes a failed task lookup for a dequeued timer and frees it while its node remains queued. The sequence requires an armed thread CPU timer and an exec failure after de_thread; the published fix establishes the use-after-free, not a reliable privilege-escalation outcome.

CVSS severityUnavailable
Unscored
EPSS probability0.13%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Linux kernel POSIX CPU timers allows local users to trigger kernel memory corruption when a non-leader thread's exec fails. After de_thread changes PID ownership, timer deletion mistakes a failed task lookup for a dequeued timer and frees it while its node remains queued. The sequence requires an armed thread CPU timer and an exec failure after de_thread; the published fix establishes the use-after-free, not a reliable privilege-escalation outcome.

The record

CVE
CVE-2026-98260
Published
Oct 6, 2026
Updated
Oct 6, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Oct 6, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 6, 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=55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 <6f1977cea3e85cd8ab55fb337d3e1725fe61d1ce
  2. Affected versionversion=55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 <75aa08b93c65766040f9ca99f41ac85ad22596b6
  3. Affected versionversion=55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 <acb03d3881818581052924a9bbbe92b8741ed448
  4. Affected versionversion=55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 <d602877baf36c43c788a5f472c977e0be414029f
  5. Affected versionversion=55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 <d9ae467e617ca29b825493a362bf0d75ad5f4ac3
  6. Affected versionversion=5.7

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 <6f1977cea3e85cd8ab55fb337d3e1725fe61d1ce; version=55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 <75aa08b93c65766040f9ca99f41ac85ad22596b6; version=55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 <acb03d3881818581052924a9bbbe92b8741ed448; version=55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 <d602877baf36c43c788a5f472c977e0be414029f; version=55e8c8eb2c7b6bf30e99423ccfe7ca032f498f59 <d9ae467e617ca29b825493a362bf0d75ad5f4ac3; version=5.7

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)
Vectorlocal
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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