CVE-2023-53490

Local system crash via MPTCP accept-disconnect race

Published Oct 1, 2025 · Updated Oct 1, 2025

Use-after-free in the Linux kernel MPTCP subsystem allows local users to crash the system by racing accept and disconnect operations. mptcp_stream_accept() can retain a request after mptcp_subflow_queue_clean() releases the listener lock and destroys its MPTCP socket. An unprivileged local process must issue accept() concurrently with disconnect(), shutdown(), or close() on the same listener; the race causes a kernel NULL-pointer dereference and system crash.

CVSS severity7.8
High
EPSS probability0.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in the Linux kernel MPTCP subsystem allows local users to crash the system by racing accept and disconnect operations. mptcp_stream_accept() can retain a request after mptcp_subflow_queue_clean() releases the listener lock and destroys its MPTCP socket. An unprivileged local process must issue accept() concurrently with disconnect(), shutdown(), or close() on the same listener; the race causes a kernel NULL-pointer dereference and system crash.

The record

CVE
CVE-2023-53490
Published
Oct 1, 2025
Updated
Oct 1, 2025
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 1, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 1, 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=2a6a870e44dd88f1a6a2893c65ef756a9edfb4c7 <511b90e39250135a7f900f1c3afbce25543018a2
  2. Affected versionversion=2a6a870e44dd88f1a6a2893c65ef756a9edfb4c7 <b2b4c84eb7149f34c0f25f17042d095ba5357d68
  3. Affected versionversion=6.3
  4. Affected versionversion=64b66601308dae6105fbde964a339462a29c2a73
  5. Affected versionversion=b45d8f5375eda3ddc89fe529b58bb643917bd87b <ded9f5551ce5cafa3c41c794428c27a0d0a00542

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=2a6a870e44dd88f1a6a2893c65ef756a9edfb4c7 <511b90e39250135a7f900f1c3afbce25543018a2; version=2a6a870e44dd88f1a6a2893c65ef756a9edfb4c7 <b2b4c84eb7149f34c0f25f17042d095ba5357d68; version=6.3; version=64b66601308dae6105fbde964a339462a29c2a73; version=b45d8f5375eda3ddc89fe529b58bb643917bd87b <ded9f5551ce5cafa3c41c794428c27a0d0a00542

Published CVSS scores

7.8Linux Kernel CVE TeamCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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

T1499Endpoint Denial of Service

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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