How severe is CVE-2021-28664?

No CVSS score has been assigned to CVE-2021-28664 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2021-28664?

CVE-2021-28664 affects the following packages: :unknown: (Android). Ecosystems affected: Android.

How do I fix CVE-2021-28664?

Update :unknown: to SoCVersion:2021-05-05 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-28664 is resolved across your whole dependency graph.

How do I detect CVE-2021-28664 in my Android dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for :unknown:, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2021-28664 if there is no patch (or I can't update yet)?

Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable.

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 5.4%, placing it in the 93th 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.

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

CVE-2021-28664 was published on May 1, 2021 and was last updated on October 23, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 Android

CISA KEV · ACTIVELY EXPLOITED

CVE-2021-28664

CVE-2021-28664 is a Out-of-bounds Write vulnerability in :unknown:. It is in CISA's Known Exploited Vulnerabilities catalog (added 2021-11-03) — treat it as actively exploited and patch now. A fix is available for :unknown: — see the affected versions and patch details below.

Also known asA-174588870

Published

May 1, 2021

Updated

Oct 23, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

2 known

Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, CISA KEV, FIRST.org (EPSS)

Exploitation Status

Actively exploited in the wild

Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2021-11-03. Federal agencies were required to remediate by 2021-11-17.
A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2021-28664.

EPSS Exploitation Probability

via FIRST.org ↗

5.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs93th percentile — riskier than 93% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

1 pkg affected

📦:unknown:

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Android packages — download data is not available via public APIs for these ecosystems.

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 Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦Android	`:unknown:`	≥ SoCVersion:0&&< SoCVersion:2021-05-05	SoCVersion:2021-05-05

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

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for :unknown:, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update :unknown: to SoCVersion:2021-05-05 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-28664 is resolved across your whole dependency graph.
Workarounds
Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable.

Frequently Asked Questions

In kbase_mem_flags_change of mali_kbase_mem_linux.c, there is a possible overlapping kernel memory regions due to a use after free. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.

O3 Security · Impact-Aware SCA

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CVE-2021-28664

Exploitation Status

Actively exploited in the wild

EPSS Exploitation Probability

Real-World Exposure

Description

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Frequently Asked Questions

Is CVE-2021-28664 in your dependencies?