CVE-2026-64475
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 the Linux kernel, the following vulnerability has been resolved: vfio/pci: Release the VGA arbiter client on register_device() failure The re-order in the Fixes commit below displaced vfio_pci_vga_init() as the last failure point of what is now vfio_pci_core_register_device() without introducing an unwind for the VGA arbiter registration. In current kernels this is mostly benign because vfio_pci_set_decode() only uses pci_dev state, but the original failure path could leave a callback with a freed vdev cookie. The stale registration also becomes unsafe again once the callback follows drvdata to the vfio device. Add the required VGA unwind callout.
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 confidenceUse-after-free vulnerability in Linux kernel's VFIO PCI driver where VGA arbiter registration is not properly unwound on register_device() failure. The reordering of code displaced vfio_pci_vga_init() as a failure point without adding the corresponding VGA arbiter cleanup, potentially leaving a stale callback pointing to freed vdev memory.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
CVSS 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
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/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.
-
Identify kernel versionRun 'uname -r' to get the running kernel versionAffected if The kernel version is within the range that contains the vulnerable code path (between introduction of vfio_pci_vga_init() displacement and the fix commit)
-
Verify vfio-pci driver is loadedRun 'lsmod | grep vfio_pci' or check '/sys/bus/pci/drivers/vfio-pci' to see if the driver is activeAffected if The vfio-pci driver is loaded and bound to any PCI devices
-
Check for VGA-capable PCI devices bound to vfio-pciExamine '/sys/bus/pci/devices/*/driver' for devices with VGA class (class 0x030000) bound to vfio-pci, or run 'lspci -nnk -d ::0300' to list VGA devicesAffected if Any VGA-class PCI device is bound to the vfio-pci driver, enabling the vulnerable vfio_pci_vga_init() code path
-
Confirm VGA arbiter registration existsCheck kernel config for CONFIG_VFIO_PCI_VGA or verify presence of '/sys/kernel/debug/vfio-pci' debugfs entry after loading the driverAffected if VFIO PCI VGA support is compiled in or available, meaning the VGA arbiter callback can be registered during device initialization
A system is affected if it runs a vulnerable kernel version with vfio-pci loaded and has any VGA-capable PCI device bound to vfio-pci, creating conditions where register_device() failure after vfio_pci_vga_init() could trigger the use-after-free.
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 dataThis kernel bug requires applying the vendor patch that adds the missing VGA arbiter unwind callout in vfio_pci_core_register_device() failure path. No userspace workaround exists; kernel-level remediation is required.
- Consultation2.0 h
- Implementation2.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,752.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-64475 — 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-2026-64475 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