CVE-2025-39856

Kernel crash via uninitialized ndev dereference

Published Sep 19, 2025 · Updated Sep 19, 2025

NULL pointer dereference in affected Linux kernels allows local users to crash the kernel through the TI CPSW2G transmit-completion path. The transmit-completion handler in drivers/net/ethernet/ti/am65-cpsw-nuss.c dereferences ndev before initialization when no transmit packets were processed. Reachability requires local low-privileged access and a TI SoC CPSW2G instance with one external Ethernet port; the resulting NULL dereference crashes the host kernel.

CVSS severity5.5
Medium
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL pointer dereference in affected Linux kernels allows local users to crash the kernel through the TI CPSW2G transmit-completion path. The transmit-completion handler in drivers/net/ethernet/ti/am65-cpsw-nuss.c dereferences ndev before initialization when no transmit packets were processed. Reachability requires local low-privileged access and a TI SoC CPSW2G instance with one external Ethernet port; the resulting NULL dereference crashes the host kernel.

The record

CVE
CVE-2025-39856
Published
Sep 19, 2025
Updated
Sep 19, 2025
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-476, T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 19, 2025CVE publishedPublication date reported by the CVE source.
  2. Sep 19, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=6.15
  2. Affected versionversion=9a369ae3d1431a83589dde57323a04692dd7fc12 <485302905bada953aadfe063320d73c892a66cbb
  3. Affected versionversion=9a369ae3d1431a83589dde57323a04692dd7fc12 <a6099f263e1f408bcc7913c9df24b0677164fc5d

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=6.15; version=9a369ae3d1431a83589dde57323a04692dd7fc12 <485302905bada953aadfe063320d73c892a66cbb; version=9a369ae3d1431a83589dde57323a04692dd7fc12 <a6099f263e1f408bcc7913c9df24b0677164fc5d

Published CVSS scores

5.5CISA-ADPCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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