CVE-2023-52973

Local freed-memory read via stale vc_data pointer

Published Mar 27, 2025 · Updated Aug 5, 2026

Use-after-free in vc_screen in Linux allows local users to read freed kernel memory through a virtual-console device during concurrent deallocation. In vcs_read(), console_unlock() permits vc_deallocate() to free the current vc_data object before vcs_size() dereferences the stale pointer. Exploitation requires local low-privileged access and winning this race; the documented failure is a four-byte invalid read from freed kernel heap memory.

CVSS severity7.8
High
EPSS probability0.29%
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 vc_screen in Linux allows local users to read freed kernel memory through a virtual-console device during concurrent deallocation. In vcs_read(), console_unlock() permits vc_deallocate() to free the current vc_data object before vcs_size() dereferences the stale pointer. Exploitation requires local low-privileged access and winning this race; the documented failure is a four-byte invalid read from freed kernel heap memory.

The record

CVE
CVE-2023-52973
Published
Mar 27, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-416
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 27, 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=2.6.38
  2. Affected versionversion=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <226fae124b2dac217ea5436060d623ff3385bc34
  3. Affected versionversion=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <55515d7d8743b71b80bfe68e89eb9d92630626ab
  4. Affected versionversion=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <6332f52f44b9776568bf3c0b714ddfb0bb175e78
  5. Affected versionversion=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <8506f16aae9daf354e3732bcfd447e2a97f023df
  6. Affected versionversion=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <af79ea9a2443016f64d8fd8d72020cc874f0e066
  7. Affected versionversion=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <d0332cbf53dad06a22189cc341391237f4ea6d9f
  8. Affected versionversion=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <fc9e27f3ba083534b8bbf72ab0f5c810ffdc7d18

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=2.6.38; version=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <226fae124b2dac217ea5436060d623ff3385bc34; version=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <55515d7d8743b71b80bfe68e89eb9d92630626ab; version=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <6332f52f44b9776568bf3c0b714ddfb0bb175e78; version=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <8506f16aae9daf354e3732bcfd447e2a97f023df; version=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <af79ea9a2443016f64d8fd8d72020cc874f0e066; version=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <d0332cbf53dad06a22189cc341391237f4ea6d9f; version=ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff <fc9e27f3ba083534b8bbf72ab0f5c810ffdc7d18

Published CVSS scores

7.8CISA-ADPCVSS: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

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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-416Use After Free

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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