CVE-2026-23221
HighIn the Linux kernel, the following vulnerability has been resolved: bus: fsl-mc: fix use-after-free in driver_override_show() The driver_override_show() function reads the driver_override string without holding the device_lock. However, driver_override_store() uses driver_set_override(), which modifies and frees the string while holding the device_lock. This can result in a concurrent use-after-free if the string is freed by the store function while being read by the show function. Fix this by holding the device_lock around the read operation.
CVSS 3.1 score
7.8
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness type
CWE-416CVE-2026-23221 is a Use After Free vulnerability
What is Use After Free?
The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. Learn more on MITRE CWE
Affected versions
Linux kernel versions
5.10
and later are affected. Fixed in
5.15.201,
6.1.164,
6.6.127,
6.12.74,
6.18.11,
6.19.1,
7.0
and their respective stable series.
References
The following references provide additional information about CVE-2026-23221 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/148891e95014b5dc5878acefa57f1940c281c431
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PatchKernel patch commithttps://git.kernel.org/stable/c/1d6bd6183e723a7b256ff34bbb5b498b5f4f2ec0
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PatchKernel patch commithttps://git.kernel.org/stable/c/a2ae33e1c6361e960a4d00f7cf75d880b54f9528
Frequently asked questions
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What is CVE-2026-23221?
CVE-2026-23221 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 , classified as an Use After Free flaw (CWE-416) . It affects Linux kernel versions from 5.10 onward and has been patched in 5.15.201, 6.1.164, 6.6.127 and others. CVE-2026-23221 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2026-23221?
CVE-2026-23221 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. -
Is there a patch available for CVE-2026-23221?
Yes — CVE-2026-23221 has been patched. Fixed versions include 5.15.201, 6.1.164, 6.6.127 and others. If you are running Linux kernel 5.10 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-23221 actively exploited?
No — CVE-2026-23221 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is Use After Free (CWE-416)?
The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. View CWE-416 on MITRE CWE →