CVE-2023-21166
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedIn RGXBackingZSBuffer of rgxta3d.c, there is a possible arbitrary code execution due to a use after free. This could lead to local escalation of privilege in the kernel with no additional execution privileges needed. User interaction is not needed for exploitation.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceA use-after-free vulnerability exists in the RGXBackingZSBuffer function of the rgxta3d.c kernel driver (likely ARM Mali/PowerVR graphics driver). The bug allows a local attacker to achieve arbitrary code execution at kernel privilege level without requiring any user interaction.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE dataall versionsCVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify GPU hardware vendorCheck /sys/class/misc/mali0/device/name or /proc/pvr/version for GPU information, or inspect dmesg output for 'Mali' or 'rgx' stringsAffected if Device uses ARM Mali GPU hardware (rgxta3d driver is ARM-specific)
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Locate the Mali kernel driver moduleRun 'lsmod | grep -i mali' or check /sys/module/ for a directory starting with 'mali' or 'rgx'Affected if Mali GPU kernel module is loaded on the device
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Check kernel versionRun 'uname -r' or check /proc/versionAffected if Kernel version is unpatched (this driver vulnerability is in kernel-space)
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Verify driver version if accessibleCheck /sys/module/*mali*/version or /sys/module/*rgx*/version, or look for the driver file in /lib/modules/ and inspect its version infoAffected if Driver version does not include the CVE-2023-21166 patch (patch level before February 2023 Android security bulletin)
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Check for known vulnerable functionInspect /proc/kallsyms for 'RGXBackingZSBuffer' symbol - if present without KASLR offset randomization, the function exists in kernelAffected if The vulnerable function RGXBackingZSBuffer is exposed in the kernel symbol table
Device is affected if it runs Android with an unpatched ARM Mali GPU kernel driver containing the RGXBackingZSBuffer function, regardless of Android version since all versions are impacted until the vendor patch is applied.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataApply the vendor-provided kernel/driver patch through system update; this is a kernel-space vulnerability requiring a driver update rather than application-level remediation.
- Consultation4.0 h
- Implementation16.0 h
- Testing12.0 h
- Review / QA6.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $10,496.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2023-21166 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2023-21166 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
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