Linux Kernel up to 6.16.5/6.17-rc4 net null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.16.5/6.17-rc4. This affects an unknown part of the component net. Such manipulation leads to null pointer dereference. This vulnerability is uniquely identified as CVE-2025-39856. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.16.5/6.17-rc4. It has been rated as critical. Affected by this issue is an unknown function of the component net. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: net: ethernet: ti: am65-cpsw-nuss: Fix null pointer dereference for ndev In the TX completion packet stage of TI SoCs with CPSW2G instance, which has single external ethernet port, ndev is accessed without being initialized if no TX packets have been processed. It results into null pointer dereference, causing kernel to crash. Fix this by having a check on the number of TX packets which have been processed.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2025-39856 since 04/16/2025. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 265887 (Linux Distros Unpatched Vulnerability : CVE-2025-39856), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.16.6 or 6.17-rc5 eliminates this vulnerability. Applying the patch 485302905bada953aadfe063320d73c892a66cbb/a6099f263e1f408bcc7913c9df24b0677164fc5d 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 (265887) and CERT Bund (WID-SEC-2025-2099). Once again VulDB remains the best source for vulnerability data.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • IBM QRadar SIEM
  • SUSE openSUSE
  • RESF Rocky Linux
  • Open Source Linux Kernel
  • Dell Secure Connect Gateway

Productinfo

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Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
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: 265887
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-39856

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.16.6/6.17-rc5
Patch: 485302905bada953aadfe063320d73c892a66cbb/a6099f263e1f408bcc7913c9df24b0677164fc5d

Timelineinfo

04/16/2025 CVE reserved
09/19/2025 +156 days Advisory disclosed
09/19/2025 +0 days VulDB entry created
12/22/2025 +94 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-39856 (🔒)
GCVE (CVE): GCVE-0-2025-39856
GCVE (VulDB): GCVE-100-325052
CERT Bund: WID-SEC-2025-2099 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 09/19/2025 18:20
Updated: 12/22/2025 10:56
Changes: 09/19/2025 18:20 (58), 09/28/2025 17:19 (2), 10/20/2025 20:58 (7), 11/12/2025 05:12 (1), 11/29/2025 07:12 (1), 12/12/2025 02:04 (10), 12/22/2025 10:56 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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