CVE-2025-38708
HighIn the Linux kernel, the following vulnerability has been resolved: drbd: add missing kref_get in handle_write_conflicts With `two-primaries` enabled, DRBD tries to detect "concurrent" writes and handle write conflicts, so that even if you write to the same sector simultaneously on both nodes, they end up with the identical data once the writes are completed. In handling "superseeded" writes, we forgot a kref_get, resulting in a premature drbd_destroy_device and use after free, and further to kernel crashes with symptoms. Relevance: No one should use DRBD as a random data generator, and apparently all users of "two-primaries" handle concurrent writes correctly on layer up. That is cluster file systems use some distributed lock manager, and live migration in virtualization environments stops writes on one node before starting writes on the other node. Which means that other than for "test cases", this code path is never taken in real life. FYI, in DRBD 9, things are handled differently nowadays. We still detect "write conflicts", but no longer try to be smart about them. We decided to disconnect hard instead: upper layers must not submit concurrent writes. If they do, that's their fault.
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-2025-38708 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
4.5
and later are affected. Fixed in
5.4.297,
5.10.241,
5.15.190,
6.1.149,
6.6.103,
6.12.43,
6.15.11,
6.16.2,
6.17
and their respective stable series.
References
The following references provide additional information about CVE-2025-38708 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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Mailing List Third Party Advisory
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Mailing List Third Party Advisory
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PatchKernel patch commithttps://git.kernel.org/stable/c/00c9c9628b49e368d140cfa61d7df9b8922ec2a8
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PatchKernel patch commithttps://git.kernel.org/stable/c/0336bfe9c237476bd7c45605a36ca79c2bca62e5
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PatchKernel patch commithttps://git.kernel.org/stable/c/3a896498f6f577e57bf26aaa93b48c22b6d20c20
Frequently asked questions
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What is CVE-2025-38708?
CVE-2025-38708 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 4.5 onward and has been patched in 5.4.297, 5.10.241, 5.15.190 and others. CVE-2025-38708 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-2025-38708?
CVE-2025-38708 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-2025-38708?
Yes — CVE-2025-38708 has been patched. Fixed versions include 5.4.297, 5.10.241, 5.15.190 and others. If you are running Linux kernel 4.5 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2025-38708 actively exploited?
No — CVE-2025-38708 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 →