Advisory Details

July 17th, 2025

Linux Kernel ksmbd destroy_previous_session Null Pointer Dereference Denial-of-Service Vulnerability

ZDI-25-610
ZDI-CAN-27391

CVE ID CVE-2025-38191
CVSS SCORE 5.9, AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
AFFECTED VENDORS Linux
AFFECTED PRODUCTS Kernel
VULNERABILITY DETAILS

This vulnerability allows remote attackers to create a denial-of-service condition on affected installations of the Linux Kernel. Authentication is not required to exploit this vulnerability.

The specific flaw exists within the destroy_previous_session function. The issue results from the lack of proper validation of a pointer prior to accessing it. An attacker can leverage this vulnerability to create a denial-of-service condition on the system.

ADDITIONAL DETAILS Linux has issued an update to correct this vulnerability. More details can be found at:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=7ac5b66acafcc9292fb935d7e03790f2b8b2dc0e
DISCLOSURE TIMELINE
  • 2025-06-12 - Vulnerability reported to vendor
  • 2025-07-17 - Coordinated public release of advisory
  • 2025-07-17 - Advisory Updated
CREDIT Nicholas Zubrisky (@NZubrisky) of Trend Research
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