CVE-2024-56372

Kernel crash via first-iovec reuse

Published Jan 11, 2025 · Updated May 11, 2026

NULL pointer dereference in the Linux kernel TUN driver allows local users to crash the kernel through crafted vector writes to a TUN device. The tun_napi_alloc_frags function repeatedly reads the first iovec component instead of advancing across all components, producing a malformed socket buffer that reaches a BUG in __pskb_pull_tail. Low-privilege local access and permission to write to a TUN device are required; successful triggering interrupts the operating system through a kernel crash.

CVSS severity5.5
Medium
EPSS probability0.24%
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 the Linux kernel TUN driver allows local users to crash the kernel through crafted vector writes to a TUN device. The tun_napi_alloc_frags function repeatedly reads the first iovec component instead of advancing across all components, producing a malformed socket buffer that reaches a BUG in __pskb_pull_tail. Low-privilege local access and permission to write to a TUN device are required; successful triggering interrupts the operating system through a kernel crash.

The record

CVE
CVE-2024-56372
Published
Jan 11, 2025
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-476, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 11, 2025CVE publishedPublication date reported by the CVE source.
  2. May 11, 2026Record 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=6.4
  2. Affected versionversion=de4f5fed3f231a8ff4790bf52975f847b95b85ea <429fde2d81bcef0ebab002215358955704586457
  3. Affected versionversion=de4f5fed3f231a8ff4790bf52975f847b95b85ea <4f393ea1e2f9c3b646d00572dd92c48b1869c65f
  4. Affected versionversion=de4f5fed3f231a8ff4790bf52975f847b95b85ea <efe74dd58a72bd987b158142c904b7ef2ad132e2

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=6.4; version=de4f5fed3f231a8ff4790bf52975f847b95b85ea <429fde2d81bcef0ebab002215358955704586457; version=de4f5fed3f231a8ff4790bf52975f847b95b85ea <4f393ea1e2f9c3b646d00572dd92c48b1869c65f; version=de4f5fed3f231a8ff4790bf52975f847b95b85ea <efe74dd58a72bd987b158142c904b7ef2ad132e2

Published CVSS scores

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

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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