FKIE_CVE-2025-39838

Vulnerability from fkie_nvd - Published: 2025-09-19 16:15 - Updated: 2026-01-23 02:34
Severity ?
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
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
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1f797f062b5cf13a1c2bcc23285361baaa7c9260Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3c26a8d30ed6b53a52a023ec537dc50a6d34a67aPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/70bccd9855dae56942f2b18a08ba137bb54093a0Patch
af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2025/10/msg00008.htmlThird Party Advisory
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel 6.17
linux linux_kernel 6.17
linux linux_kernel 6.17
linux linux_kernel 6.17
debian debian_linux 11.0
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  "descriptions": [
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      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: prevent NULL pointer dereference in UTF16 conversion\n\nThere can be a NULL pointer dereference bug here. NULL is passed to\n__cifs_sfu_make_node without checks, which passes it unchecked to\ncifs_strndup_to_utf16, which in turn passes it to\ncifs_local_to_utf16_bytes where \u0027*from\u0027 is dereferenced, causing a crash.\n\nThis patch adds a check for NULL \u0027src\u0027 in cifs_strndup_to_utf16 and\nreturns NULL early to prevent dereferencing NULL pointer.\n\nFound by Linux Verification Center (linuxtesting.org) with SVACE"
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  "id": "CVE-2025-39838",
  "lastModified": "2026-01-23T02:34:16.110",
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          "baseScore": 5.5,
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