CVE-2021-47533 - Vulnerability Details - OpenCVE

In the Linux kernel, the following vulnerability has been resolved:

drm/vc4: kms: Clear the HVS FIFO commit pointer once done

Commit 9ec03d7f1ed3 ("drm/vc4: kms: Wait on previous FIFO users before a
commit") introduced a wait on the previous commit done on a given HVS
FIFO.

However, we never cleared that pointer once done. Since
drm_crtc_commit_put can free the drm_crtc_commit structure directly if
we were the last user, this means that it can lead to a use-after free
if we were to duplicate the state, and that stale pointer would even be
copied to the new state.

Set the pointer to NULL once we're done with the wait so that we don't
carry over a pointer to a free'd structure.

No CVSS v4.0

Attack Vector Local

Attack Complexity High

Privileges Required Low

Scope Unchanged

Confidentiality Impact Low

Integrity Impact Low

Availability Impact Low

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00027.

Exploitation none

Automatable no

Technical Impact partial

Vendors	Products
Linux	Linux Kernel

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

Vendors	Products
Linux	Linux Kernel

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://git.kernel.org/stable/c/2931db9a5ed219546cf2ae0546698faf78281b89
https://git.kernel.org/stable/c/d134c5ff71c7f2320fc7997f2fbbdedf0c76889a
https://lore.kernel.org/linux-cve-announce/2024052436-CVE-2021-47533-a03a@gregkh/T
https://nvd.nist.gov/vuln/detail/CVE-2021-47533
https://www.cve.org/CVERecord?id=CVE-2021-47533

History

Mon, 04 Nov 2024 12:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2024-05-24T15:09:42.683Z

Updated: 2025-05-04T07:13:00.256Z

Reserved: 2024-05-24T15:02:54.826Z

Link: CVE-2021-47533

Vulnrichment

Updated: 2024-08-04T05:39:59.620Z

NVD

Status : Awaiting Analysis

Published: 2024-05-24T15:15:16.773

Modified: 2024-11-21T06:36:28.440

Link: CVE-2021-47533

Redhat

Severity : Low

Publid Date: 2024-05-24T00:00:00Z

Links: CVE-2021-47533 - Bugzilla

OpenCVE Enrichment

Updated: 2025-07-13T11:14:48Z

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