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CVE-2025-39838

Full vulnerability record from the local CVENow database.

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 NULL pointer. Found by Linux Verification Center (linuxtesting.org) with SVACE

Severity
MEDIUM
CVSS score
5.5 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2025-09-19 16:15:42.457000
Last modified
2026-10-19 21:10:00.160000
View original CVE JSON 
{
  "id": "CVE-2025-39838",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2025-09-19T16:15:42.457",
  "lastModified": "2026-10-19T21:10:00.160",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "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 '*from' is dereferenced, causing a crash.\n\nThis patch adds a check for NULL 'src' in cifs_strndup_to_utf16 and\nreturns NULL early to prevent dereferencing NULL pointer.\n\nFound by Linux Verification Center (linuxtesting.org) with SVACE"
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\ncifs: prevenir la desreferencia de puntero NULL en la conversión UTF16\n\nPuede haber un error de desreferencia de puntero NULL aquí. Se pasa NULL a __cifs_sfu_make_node sin comprobaciones, que lo pasa sin comprobar a cifs_strndup_to_utf16, que a su vez lo pasa a cifs_local_to_utf16_bytes donde se desreferencia '*from', causando un fallo.\n\nEste parche añade una comprobación para NULL 'src' en cifs_strndup_to_utf16 y devuelve NULL anticipadamente para prevenir la desreferencia del puntero NULL.\n\nEncontrado por Linux Verification Center (linuxtesting.org) con SVACE"
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          "product": "SIMATIC CN 4100",
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  "metrics": {
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          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
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        "impactScore": 3.6
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  "weaknesses": [
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      "source": "[email protected]",
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      "description": [
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}