Kernel use-after-free via freed mutex unlock
Published Sep 25, 2026 · Updated Sep 25, 2026
Use-after-free in Linux 6.18 hwmon pec_store allows attackers to trigger an unlock of a freed device mutex during error handling. After a chip-write error other than -EOPNOTSUPP, pec_store calls put_device(), which can free the device before automatic guard cleanup unlocks hwdev->lock. Reachability requires the hwmon PEC write path, the specified chip-write failure, and the final device reference to be released; the disclosed consequence is a kernel memory-safety violation.
Summary
What happened
Use-after-free in Linux 6.18 hwmon pec_store allows attackers to trigger an unlock of a freed device mutex during error handling. After a chip-write error other than -EOPNOTSUPP, pec_store calls put_device(), which can free the device before automatic guard cleanup unlocks hwdev->lock. Reachability requires the hwmon PEC write path, the specified chip-write failure, and the final device reference to be released; the disclosed consequence is a kernel memory-safety violation.
The record
- CVE
- CVE-2026-98000
- Published
- Sep 25, 2026
- Updated
- Sep 25, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 25, 2026CVE publishedPublication date reported by the CVE source.
- Sep 25, 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?
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- Affected versionversion=3ad2a7b9b15d5072139a20be84adb36776eb6c9b <01dd8b4fc2cf83c66565c0f382fb1841e9000a89
- Affected versionversion=3ad2a7b9b15d5072139a20be84adb36776eb6c9b <354ccc99b2dc8ba0cf6d4de34e520bcf6ecca5c2
- Affected versionversion=3ad2a7b9b15d5072139a20be84adb36776eb6c9b <8afab57bcdbc2186f325972e777880ac5a220f4f
- Affected versionversion=6.18
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
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Public exploit references
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Technologies
Your stack
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