Linux Kernel up to 6.1.153/6.6.107/6.12.48/6.16.8 ksmbd remaining_data_length memory corruption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.6$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.1.153/6.6.107/6.12.48/6.16.8. It has been rated as critical. This vulnerability affects the function remaining_data_length of the component ksmbd. Performing a manipulation results in memory corruption. This vulnerability was named CVE-2025-39942. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.1.153/6.6.107/6.12.48/6.16.8. This affects the function remaining_data_length of the component ksmbd. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: ksmbd: smbdirect: verify remaining_data_length respects max_fragmented_recv_size This is inspired by the check for data_offset + data_length.

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2025-39942 since 04/16/2025. The exploitability is told to be easy. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/28/2026).

The vulnerability scanner Nessus provides a plugin with the ID 269448 (Linux Distros Unpatched Vulnerability : CVE-2025-39942), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.154, 6.6.108, 6.12.49 or 6.16.9 eliminates this vulnerability. Applying the patch 196a3a7676d726ee67621ea2bf3b7815ac2685b4/d3cb3f209d35c44b7ee74f77ed27ebb28995b9ce/9644798294c7287e65a7b26e35aa6d2ce3345bcc/c64b915bb3d9339adcae5db4be2c35ffbef5e615/e1868ba37fd27c6a68e31565402b154beaa65df0 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (269448) and CERT Bund (WID-SEC-2025-2194). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Google Cloud Platform
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • Open Source Linux Kernel
  • RESF Rocky Linux
  • NetApp ActiveIQ Unified Manager
  • IBM QRadar SIEM
  • Dell NetWorker

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.6

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 269448
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-39942

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.1.154/6.6.108/6.12.49/6.16.9
Patch: 196a3a7676d726ee67621ea2bf3b7815ac2685b4/d3cb3f209d35c44b7ee74f77ed27ebb28995b9ce/9644798294c7287e65a7b26e35aa6d2ce3345bcc/c64b915bb3d9339adcae5db4be2c35ffbef5e615/e1868ba37fd27c6a68e31565402b154beaa65df0

Timelineinfo

04/16/2025 CVE reserved
10/04/2025 +171 days Advisory disclosed
10/04/2025 +0 days VulDB entry created
04/28/2026 +206 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-39942 (🔒)
GCVE (CVE): GCVE-0-2025-39942
GCVE (VulDB): GCVE-100-327033
CERT Bund: WID-SEC-2025-2194 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 10/04/2025 11:33
Updated: 04/28/2026 06:27
Changes: 10/04/2025 11:33 (59), 10/08/2025 19:51 (2), 11/24/2025 02:44 (7), 12/27/2025 00:10 (1), 01/27/2026 21:45 (11), 04/28/2026 06:27 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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