CVE-2021-28663
CVE-2021-28663 is a security flaw in Arm Mali Graphics Processing Unit (GPU), the graphics chip design in many Android phones. Someone who already has a foothold can use Arm Mali Graphics Processing Unit (GPU) to take full control of the machine. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 3 Nov 2021.[1]
Arm Mali Graphics Processing Unit (GPU) is in things households have, such as phones, computers, browsers and everyday apps, so the fix matters at home as much as at work. Arm has published a fix or advice.
Description
CISA calls it an use-after-free in Arm Mali Graphics Processing Unit (GPU). In its words: “Arm Mali Graphics Processing Unit (GPU) kernel driver contains a use-after-free vulnerability that may allow a non-privileged user to make improper operations on GPU memory to gain root privilege, and/or disclose information.”[1]
The CVE record adds: “The Arm Mali GPU kernel driver allows privilege escalation or information disclosure because GPU memory operations are mishandled, leading to a use-after-free. This affects Bifrost r0p0 through r28p0 before r29p0, Valhall r19p0 through r28p0 before r29p0, and Midgard r4p0 through r30p0.”[2]
The underlying weakness is use after free (CWE-416), in MITRE’s list of common software weaknesses.
It scores 8.8 out of 10 on the Common Vulnerability Scoring System, which rates it high, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record doesn’t list version ranges for it; Arm’s advisory has them[3]. CISA names the product as Arm Mali Graphics Processing Unit (GPU).
Every device with Arm Mali Graphics Processing Unit (GPU) needs the update.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 3 Nov 2021, 177 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 17 Nov 2021 to fix it.[1]
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 12%. That’s in the top 4% of the flaws it scores.[4]
CISA assesses it as not automatable: each attack takes some work.
CISA doesn’t say who was attacked, or how.
Fix
Arm has published a fix or advice.[3] CISA’s required action: “Apply updates per vendor instructions.”[1]
- Update Arm Mali Graphics Processing Unit (GPU) now.Install the latest update from Arm on every device that has it, and restart when asked. Then turn on automatic updates, so the next fix arrives on its own.
- If there’s no update, stop using it.CISA’s advice when a flaw being used in attacks has no fix is to stop using the product until it does.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 8.8.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 12%.[4] |
See also
Other Arm Mali Graphics Processing Unit (GPU) flaws
- CVE-2021-29256: mali GPU kernel driver use-after-free ·
- CVE-2023-26083: mali GPU kernel driver information disclosure ·
- CVE-2022-38181: mali GPU kernel driver use-after-free ·
- CVE-2022-22706: mali GPU kernel driver unspecified ·
- CVE-2021-28664: unspecified ·
Other Arm flaws
- CVE-2024-4610, Arm Mali GPU Kernel Driver: use-after-free ·
- CVE-2023-4211, Arm Mali GPU Kernel Driver: use-after-free ·
- CVE-2021-27562, Arm Trusted Firmware: out-of-bounds write ·
Other use after free flaws
- CVE-2026-109619, PHP: stale internal request-state ·
- CVE-2026-109618, PHP: memory corruption ·
- CVE-2026-68820, Microsoft Windows Ancillary Function Driver for WinSock: use-after-free ·
- CVE-2010-0249, Microsoft Internet Explorer: use-after-free ·
- CVE-2020-9715, Adobe Acrobat: use-after-free ·
Added the same day
- CVE-2021-42258, BQE BillQuick Web Suite: SQL injection ·
- CVE-2021-42013, Apache HTTP Server: path traversal ·
- CVE-2021-41773, Apache HTTP Server: path traversal ·
- CVE-2021-40539, Zoho ManageEngine: aDSelfService plus authentication bypass ·
- CVE-2021-40444, Microsoft MSHTML: remote code execution ·
Every Arm flaw on CISA’s list · Everything added in November 2021
References
- ^ Cybersecurity and Infrastructure Security Agency. “Arm Mali Graphics Processing Unit (GPU) Use-After-Free Vulnerability”. Known Exploited Vulnerabilities Catalog, added 3 Nov 2021.
- ^ National Institute of Standards and Technology. “CVE-2021-28663 Detail”. National Vulnerability Database, published 10 May 2021.
- ^ Arm. Advisories and fixes: developer.arm.com, developer.arm.com.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.121, percentile 96.1, 31 Oct 2026.
- CVE Program. “CVE-2021-28663”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.