CVE-2025-39838NULL Pointer Dereference in Linux

Severity
5.5MEDIUMNVD
EPSS
0.0%
top 95.77%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedSep 19
Latest updateApr 9

Description

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

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitability: 1.8 | Impact: 3.6

Affected Packages3 packages

NVDlinux/linux_kernel6.126.12.46+2
Debianlinux/linux_kernel< 6.1.153-1+2
CVEListV5linux/linux41d3f256c6a5e41eb32b87168399c0facd512dc01f797f062b5cf13a1c2bcc23285361baaa7c9260+3

Also affects: Debian Linux 11.0

Patches

🔴Vulnerability Details

3
GHSA
GHSA-9q78-c4fv-64q9: In the Linux kernel, the following vulnerability has been resolved: cifs: prevent NULL pointer dereference in UTF16 conversion There can be a NULL p2025-09-22
CVEList
cifs: prevent NULL pointer dereference in UTF16 conversion2025-09-19
OSV
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 poi2025-09-19

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CVE-2025-39838 — NULL Pointer Dereference in Linux | cvebase