How severe is CVE-2021-28664?

CVE-2021-28664 has a CVSS score of 8.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2021-28664?

Affected package information for CVE-2021-28664 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2021-28664?

No fixed version has been published for CVE-2021-28664 yet. Monitor the advisory for updates, apply mitigations recommended by the vendor, and use O3 Security to track when a fix becomes available in your stack.

Is CVE-2021-28664 actively exploited in the wild?

Yes. There are 2 known exploit references for CVE-2021-28664, including 2 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2021-28664?

CVE-2021-28664 has an EPSS (Exploit Prediction Scoring System) score of 0.3%, placing it in the 56th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

Is CVE-2021-28664 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2021-28664 (Arm Mali Graphics Processing Unit (GPU) Unspecified Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2021-11-03. CISA required all US federal civilian agencies to remediate this vulnerability by 2021-11-17. The required action was: Apply updates per vendor instructions. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

What type of vulnerability is CVE-2021-28664?

CVE-2021-28664 is classified as Out-of-bounds Write (CWE-787). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

Which products and versions are affected by CVE-2021-28664?

CVE-2021-28664 affects arm bifrost gpu kernel driver; arm midgard gpu kernel driver; arm valhall gpu kernel driver. Check the affected-products list on this page against your deployed version to confirm exposure.

When was CVE-2021-28664 published, and has it been updated?

CVE-2021-28664 was published on May 10, 2021 and was last updated on November 3, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CISA KEV·Added 2021-11-03 — agencies required to remediate by 2021-11-17

CVE-2021-28664

HIGH

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.…

Published

May 10, 2021

Updated

Nov 3, 2025

Affected

0 pkgs

Patched

None yet

Exploits

2 known

EPSS Exploitation Probability

via FIRST.org ↗

0.3%probability of exploitation in next 30 days

Lower Risk56th percentile0.00%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Description

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.

Affected Products

3 products · 3 configurations

Application

bifrost gpu kernel driverarm

≥ r0p0 && < r29p0

range

Application

midgard gpu kernel driverarm

≥ r8p0 && < r31p0

range

Application

valhall gpu kernel driverarm

≥ r19p0 && < r29p0

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

The Arm Mali GPU kernel driver allows privilege escalation or a denial o…

source.android.comGoogle-sheetMay 2021

The Arm Mali GPU kernel driver allows privilege escalation or a denial o…

cisa.govCISANov 2021

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2021-28664 in your stack?

O3 detects CVE-2021-28664 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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