CVE-2021-47659 drm/plane: Move range check for format_count earlier

What is CVE-2021-47659?

CVE-2021-47659 is a medium-severity memory corruption vulnerability in Linux kernel, published on 26 Feb 2025. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

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

drm/plane: Move range check for format_count earlier

While the check for format_count > 64 in __drm_universal_plane_init() shouldn't be hit (it's a WARN_ON), in its current position it will then leak the plane->format_types array and fail to call drm_mode_object_unregister() leaking the modeset identifier. Move it to the start of the function to avoid allocating those resources in the first place.

Which versions are affected by CVE-2021-47659?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2021-47659?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2021-47659 being exploited?

There is no known exploitation of CVE-2021-47659 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2021-47659, GHSA-9r29-7c4x-xw3r, UBUNTU-CVE-2021-47659.