CVE-2025-39838

In the Linux kernel, the following vulnerability has been resolved: cifs: prevent NULL pointer dereference in UTF16 conversion There can be a NULL pointer dereference bug here. NULL is passed to __cifs_sfu_make_node without checks, which passes it unchecked to cifs_strndup_to_utf16, which in turn passes it to cifs_local_to_utf16_bytes where '*from' is dereferenced, causing a crash. This patch adds a check for NULL 'src' in cifs_strndup_to_utf16 and returns NULL early to prevent dereferencing NULL pointer. Found by Linux Verification Center (linuxtesting.org) with SVACE

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/1f797f062b5cf13a1c2bcc23285361baaa7c9260	Patch
https://git.kernel.org/stable/c/3c26a8d30ed6b53a52a023ec537dc50a6d34a67a	Patch
https://git.kernel.org/stable/c/70bccd9855dae56942f2b18a08ba137bb54093a0	Patch
https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html	Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc1::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc2::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc3::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc4::::::

Configuration 2 (hide)

cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

History

No history.

Information

Published : 2025-09-19 16:15

Updated : 2026-01-23 02:34

NVD link : CVE-2025-39838

Mitre link : CVE-2025-39838

CVE.ORG link : CVE-2025-39838

JSON object : View

Products Affected

debian

debian_linux

linux

linux_kernel

CWE

CWE-476

NULL Pointer Dereference

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