What is CVE-2021-28664?

CVE-2021-28664 is a high-severity vulnerability in Arm Bifrost GPU Kernel Driver, classified under Out-of-bounds Write. CVSS score: 8.8/10. Published 2021-05-10.

How severe is CVE-2021-28664?

High severity. CVSS v3 base score is 8.8 out of 10.

Is CVE-2021-28664 known to be exploited?

Yes. CVE-2021-28664 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating it is being actively exploited. 17 public proof-of-concept repositories are indexed.

Buffer overflow in Arm Bifrost GPU Kernel Driver

CVE-2021-28664

The Arm Mali GPU kernel driver allows privilege escalation or a denial of service (memory corruption) because an unprivileged user can achieve read/write access to read-only pages. This affects Bifrost r0p0 through r29p0 before r30p0, Valhall r19p0 through r29p0 before r30p0, and Midgard r8p0 through r30p0 before r31p0.

Vulnerability class: Buffer Overflow

Published 2021-05-10 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.054 (92.6th percentile), scored 2026-10-19.

Low probability of exploitation in the next 30 days, but still tracked. 93rd percentile — 92.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.054 · newest: 0.054 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2021-11-03. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2021-11-17.

Required action: Apply updates per vendor instructions.

Public proof-of-concept exploits

References

developer.arm.com/support/arm-security-updates (Vendor Advisory)
developer.arm.com/support/arm-security-updates/mali-gpu-kernel-driver (Vendor Advisory)
developer.arm.com/Arm Security Center/Mali GPU Driver Vulnerabilities (Vendor Advisory)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)

Frequently asked questions

What is CVE-2021-28664?: CVE-2021-28664 is a high-severity vulnerability in Arm Bifrost GPU Kernel Driver, classified under Out-of-bounds Write. CVSS score: 8.8/10. Published 2021-05-10.
How severe is CVE-2021-28664?: High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2021-28664 known to be exploited?: Yes. CVE-2021-28664 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating it is being actively exploited. 17 public proof-of-concept repositories are indexed.