CVE-2023-28327

Local system crash via unassociated diagnostic skb

Published Apr 19, 2023 · Updated Mar 19, 2025

NULL pointer dereference in Linux Kernel UNIX socket diagnostics allows local users to crash the system through a crafted Netlink request. unix_diag_get_exact allocates a response skb without an associated socket, then UID reporting dereferences that missing socket while resolving its user namespace. Low-privileged local access is required, and successful triggering causes a kernel oops and service interruption rather than data disclosure or modification.

CVSS severity5.5
Medium
EPSS probability0.19%
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 Linux Kernel UNIX socket diagnostics allows local users to crash the system through a crafted Netlink request. unix_diag_get_exact allocates a response skb without an associated socket, then UID reporting dereferences that missing socket while resolving its user namespace. Low-privileged local access is required, and successful triggering causes a kernel oops and service interruption rather than data disclosure or modification.

The record

CVE
CVE-2023-28327
Published
Apr 19, 2023
Updated
Mar 19, 2025
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-476, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 19, 2023CVE publishedPublication date reported by the CVE source.
  2. Mar 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=Linux

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=Linux

Published CVSS scores

5.5Canonical UbuntuCVSS: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

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 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
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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