CVE-2021-47659

Resource leak via late format-count validation

Published Feb 26, 2025 · Updated May 11, 2026

Resource leak in Linux kernel DRM plane initialization allows local users to exhaust kernel memory via an oversized format list. When __drm_universal_plane_init() receives format_count greater than 64, it allocates plane->format_types and a modeset identifier before returning at WARN_ON without unregistering them. Low-privilege local access is required, and repeated triggering can deplete kernel resources until service is interrupted.

CVSS severity5.5
Medium
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource leak in Linux kernel DRM plane initialization allows local users to exhaust kernel memory via an oversized format list. When __drm_universal_plane_init() receives format_count greater than 64, it allocates plane->format_types and a modeset identifier before returning at WARN_ON without unregistering them. Low-privilege local access is required, and repeated triggering can deplete kernel resources until service is interrupted.

The record

CVE
CVE-2021-47659
Published
Feb 26, 2025
Updated
May 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.001
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 26, 2025CVE publishedPublication date reported by the CVE source.
  2. May 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=4.14
  2. Affected versionversion=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <1e29d829ad51d1472dd035487953a6724b56fc33
  3. Affected versionversion=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <4ab7e453a3ee88c274cf97bee9487ab92a66d313
  4. Affected versionversion=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <4b674dd69701c2e22e8e7770c1706a69f3b17269
  5. Affected versionversion=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <787163d19bc3cdc6ca4b96223f62208534d1cf6b
  6. Affected versionversion=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <978e3d023256bfaf34a0033d40c94e8a8e70cf3c
  7. Affected versionversion=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <ad6dd7a2bac86118985c7b3426e175b9d3c1ec4f
  8. Affected versionversion=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <b5cd108143513e4498027b96ec4710702d186f11

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=4.14; version=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <1e29d829ad51d1472dd035487953a6724b56fc33; version=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <4ab7e453a3ee88c274cf97bee9487ab92a66d313; version=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <4b674dd69701c2e22e8e7770c1706a69f3b17269; version=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <787163d19bc3cdc6ca4b96223f62208534d1cf6b; version=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <978e3d023256bfaf34a0033d40c94e8a8e70cf3c; version=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <ad6dd7a2bac86118985c7b3426e175b9d3c1ec4f; version=e6fc3b68558e4c6d8d160b5daf2511b99afa8814 <b5cd108143513e4498027b96ec4710702d186f11

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

T1499.001OS Exhaustion Flood

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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