CVE-2021-47253

Local denial of service via resume memory leak

Published May 21, 2024 · Updated Aug 11, 2026

Memory leakage in the AMD display driver in Linux allows local users to exhaust kernel memory through repeated suspend and resume cycles. During resume, dm_resume calls dm_dmub_hw_init, which reaches dc_dmub_srv_create and performs a fresh kzalloc for an already allocated DMUB DC wrapper. Exploitation requires an AMD display configuration using DMUB and permission to trigger repeated suspend and resume cycles, eventually interrupting service through memory exhaustion.

CVSS severity5.5
Medium
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

Memory leakage in the AMD display driver in Linux allows local users to exhaust kernel memory through repeated suspend and resume cycles. During resume, dm_resume calls dm_dmub_hw_init, which reaches dc_dmub_srv_create and performs a fresh kzalloc for an already allocated DMUB DC wrapper. Exploitation requires an AMD display configuration using DMUB and permission to trigger repeated suspend and resume cycles, eventually interrupting service through memory exhaustion.

The record

CVE
CVE-2021-47253
Published
May 21, 2024
Updated
Aug 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-401, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 21, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 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=5.6
  2. Affected versionversion=8c7aea404d55dabc71df792c850aed5536ece2fd <9e8c2af010463197315fa54a6c17e74988b5259c
  3. Affected versionversion=8c7aea404d55dabc71df792c850aed5536ece2fd <aa000f828e60ac15d6340f606ec4a673966f5b0b
  4. Affected versionversion=8c7aea404d55dabc71df792c850aed5536ece2fd <c5699e2d863f58221044efdc3fa712dd32d55cde

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.6; version=8c7aea404d55dabc71df792c850aed5536ece2fd <9e8c2af010463197315fa54a6c17e74988b5259c; version=8c7aea404d55dabc71df792c850aed5536ece2fd <aa000f828e60ac15d6340f606ec4a673966f5b0b; version=8c7aea404d55dabc71df792c850aed5536ece2fd <c5699e2d863f58221044efdc3fa712dd32d55cde

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 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-401Missing Release of Memory after Effective Lifetime
T1499.004Endpoint Denial of Service: Application or System Exploitation

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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