CVE-2023-53836

Local privilege escalation via sockmap refcount race

Published Dec 9, 2025 · Updated Aug 5, 2026

Use-after-free in Linux kernel sockmap handling from 5.13 allows local users to crash the kernel or gain privileges via a receive race. sk_psock_queue_msg places an skb on ingress_msg without first taking another reference, letting recvmsg consume and free it before backlog skb_dequeue uses it. Reachability requires local syscall access and a sockmap-enrolled socket; exploitation can panic the host or elevate a process to kernel privileges.

CVSS severity7.8
High
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

Use-after-free in Linux kernel sockmap handling from 5.13 allows local users to crash the kernel or gain privileges via a receive race. sk_psock_queue_msg places an skb on ingress_msg without first taking another reference, letting recvmsg consume and free it before backlog skb_dequeue uses it. Reachability requires local syscall access and a sockmap-enrolled socket; exploitation can panic the host or elevate a process to kernel privileges.

The record

CVE
CVE-2023-53836
Published
Dec 9, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 9, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 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=5.13
  2. Affected versionversion=799aa7f98d53e0f541fa6b4dc9aa47b4ff2178e3 <65ad600b9bde68d2d28709943ab00b51ca8f0a1d
  3. Affected versionversion=799aa7f98d53e0f541fa6b4dc9aa47b4ff2178e3 <923877254f002ae87d441382bb1096d9e773d56d
  4. Affected versionversion=799aa7f98d53e0f541fa6b4dc9aa47b4ff2178e3 <a454d84ee20baf7bd7be90721b9821f73c7d23d9
  5. Affected versionversion=799aa7f98d53e0f541fa6b4dc9aa47b4ff2178e3 <e6b5e47adb9166e732cdf7e6e034946e3f89f36d

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.13; version=799aa7f98d53e0f541fa6b4dc9aa47b4ff2178e3 <65ad600b9bde68d2d28709943ab00b51ca8f0a1d; version=799aa7f98d53e0f541fa6b4dc9aa47b4ff2178e3 <923877254f002ae87d441382bb1096d9e773d56d; version=799aa7f98d53e0f541fa6b4dc9aa47b4ff2178e3 <a454d84ee20baf7bd7be90721b9821f73c7d23d9; version=799aa7f98d53e0f541fa6b4dc9aa47b4ff2178e3 <e6b5e47adb9166e732cdf7e6e034946e3f89f36d

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.

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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

T1068Exploitation for Privilege Escalation

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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