CVE-2025-39838 (GCVE-0-2025-39838)

Vulnerability from cvelistv5 – Published: 2025-09-19 15:26 – Updated: 2026-05-12 12:07
VLAI
Title
cifs: prevent NULL pointer dereference in UTF16 conversion
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
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 41d3f256c6a5e41eb32b87168399c0facd512dc0 , < 1f797f062b5cf13a1c2bcc23285361baaa7c9260 (git)
Affected: 41d3f256c6a5e41eb32b87168399c0facd512dc0 , < 3c26a8d30ed6b53a52a023ec537dc50a6d34a67a (git)
Affected: 41d3f256c6a5e41eb32b87168399c0facd512dc0 , < 70bccd9855dae56942f2b18a08ba137bb54093a0 (git)
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Linux Linux Affected: 6.12
Unaffected: 0 , < 6.12 (semver)
Unaffected: 6.12.46 , ≤ 6.12.* (semver)
Unaffected: 6.16.6 , ≤ 6.16.* (semver)
Unaffected: 6.17 , ≤ * (original_commit_for_fix)
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Siemens SIMATIC CN 4100 Affected: 0 , < V5.0 (custom)
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.