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
No CVSS data available.
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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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.