CVE-2026-21733
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 · uneditedSoftware installed and run as a non-privileged user may conduct improper GPU system calls to gain write permission to read-only wrapped user-mode memory and files. This is caused by improper handling of GPU memory reservation protections.
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 · moderate confidenceA vulnerability in GPU system call handling allows non-privileged users to bypass read-only memory protections through improper GPU memory reservation handling, potentially enabling write access to protected user-mode memory and files.
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 data< 25.3= 25.3CVSS 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
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- Low
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L
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.
-
Identify installed GPU softwareList all GPU drivers, runtimes, and related packages on the system. On Linux, check /usr/local/bin, /usr/bin for nvidia-smi, amdgpu-specific tools, intel-gpu-tools, or use 'lsmod' to list loaded kernel modules. On Windows, check Programs and Features for GPU driver entries.Affected if No GPU-related software is found (not affected) or GPU software is present (potential target)
-
Determine GPU driver/runtime versionRun vendor-provided tools to query version: nvidia-smi (NVIDIA), clinfo or cat /sys/class/drm/card*/device/version (AMD), intel_gpu_top or ls /sys/bus/pci/drivers/i915 (Intel). Compare this version against the vendor's official CVE advisory for CVE-2026-21733.Affected if The installed version falls within the vulnerable range stated in the vendor advisory, or version cannot be determined and GPU software is present
-
Verify non-privileged user GPU accessCheck if untrusted or non-privileged users can invoke GPU system calls. Review /dev/dri/* permissions, GPU group membership (e.g., 'video' or 'render' group), and check if GPU device files are world-readable or accessible by users outside trusted groups.Affected if Non-privileged or untrusted users have read or execute access to GPU device nodes or can invoke GPU system calls
-
Review GPU memory allocation behaviorMonitor or audit GPU memory reservation calls. On Linux, use 'strace -e gpu_*,drm_*' on GPU applications or review kernel logs (dmesg) for unusual GPU memory map requests. Look for allocations requesting both read and write flags on memory regions marked as read-only in the process.Affected if Applications or processes can allocate GPU memory with write access to regions that should be read-only protected, or unexpected memory reservation patterns are observed
-
Audit for suspicious GPU system call activityEnable auditing for GPU-related system calls (ioctls to /dev/dri/*, /dev/nvidia*). Use 'auditd' rules or 'perf trace' targeting GPU device files. Look for patterns indicating read-only protection bypass, such as repeated write attempts to reserved read-only memory regions.Affected if Audit logs reveal GPU system calls attempting to write to protected read-only memory regions, or abnormal patterns of GPU memory reservation calls from non-privileged processes
The environment is affected if a vulnerable version of GPU driver/runtime software is installed AND non-privileged users have access to GPU system calls, as the flaw allows bypassing read-only memory protections through improper GPU memory reservation handling.
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 data25.3
Apply vendor-provided patches or updates to the affected GPU driver/runtime software; until patches are available, restrict untrusted users' access to GPU resources and monitor for suspicious GPU system call activity.
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,176.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-21733 — 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-2026-21733 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
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- 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
- No spam, self-promotion, credentials, or personal data