CVE-2021-47533

Use-after-free via stale HVS commit pointer

Published May 24, 2024 · Updated Aug 5, 2026

Use-after-free in Linux vc4 KMS 5.12 through 5.15.6 allows local users to access freed kernel memory by duplicating DRM state. The HVS FIFO state retains a completed drm_crtc_commit pointer after drm_crtc_commit_put can free the object, and state duplication copies the dangling pointer. The condition requires local low-privileged access and the vc4 graphics path; published records do not document a concrete exploit outcome.

CVSS severity7.8
High
EPSS probability0.22%
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 vc4 KMS 5.12 through 5.15.6 allows local users to access freed kernel memory by duplicating DRM state. The HVS FIFO state retains a completed drm_crtc_commit pointer after drm_crtc_commit_put can free the object, and state duplication copies the dangling pointer. The condition requires local low-privileged access and the vc4 graphics path; published records do not document a concrete exploit outcome.

The record

CVE
CVE-2021-47533
Published
May 24, 2024
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-416
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 24, 2024CVE 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=5.12
  2. Affected versionversion=9ec03d7f1ed394897891319a4dda75f52c5d292d <2931db9a5ed219546cf2ae0546698faf78281b89
  3. Affected versionversion=9ec03d7f1ed394897891319a4dda75f52c5d292d <d134c5ff71c7f2320fc7997f2fbbdedf0c76889a

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.12; version=9ec03d7f1ed394897891319a4dda75f52c5d292d <2931db9a5ed219546cf2ae0546698faf78281b89; version=9ec03d7f1ed394897891319a4dda75f52c5d292d <d134c5ff71c7f2320fc7997f2fbbdedf0c76889a

Published CVSS scores

7.8kernel.orgCVSS: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

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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