NVD / CVE Program· CNA Linux

CVE-2026-46036: vfio/cdx: Serialize VFIO_DEVICE_SET_IRQS with a per-device mutex

Noroxi assessment

Priority: Monitor (action score 31/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.13% (FIRST EPSS).
Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
Fixed version: Linux Linux 670e8864b1a218d72f08db40d0103adf38fa1d9b, 7530f34ec0ca1438d45a75dcb43183a1cc92eced, 7b436ade16cc81095d79b79f8efa3af0a4f5c5a2.

Low priority for now. Upgrade to Linux Linux 670e8864b1a218d72f08db40d0103adf38fa1d9b, 7530f34ec0ca1438d45a75dcb43183a1cc92eced, 7b436ade16cc81095d79b79f8efa3af0a4f5c5a2 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: vfio/cdx: Serialize VFIO_DEVICE_SET_IRQS with a per-device mutex vfio_cdx_set_msi_trigger() reads vdev->config_msi and operates on the vdev->cdx_irqs array based on its value, but provides no serialization against concurrent VFIO_DEVICE_SET_IRQS ioctls. Two callers can race such that one observes config_msi as set while another clears it and frees cdx_irqs via vfio_cdx_msi_disable(), resulting in a use-after-free of the cdx_irqs array. Add a cdx_irqs_lock mutex to struct vfio_cdx_device and acquire it in vfio_cdx_set_msi_trigger(), which is the single chokepoint through which all updates to config_msi, cdx_irqs, and msi_count flow, covering both the ioctl path and the close-device cleanup path. This keeps the test of config_msi atomic with the subsequent enable, disable, or trigger operations. Drop the pre-call !cdx_irqs test from vfio_cdx_irqs_cleanup() as part of this change: the optimization it provided is redundant with the !config_msi early-return inside vfio_cdx_msi_disable(), and leaving the test in place would be an unsynchronized read of state the new lock is meant to protect.

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

Published: May 27, 2026
Updated: Aug 5, 2026
EPSS: 0.1% · 3th percentile
CWE: CWE-416

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 31 / 40 · 7.8 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.1%

CNA vs NVD score

NVD: —
CNA · Linux: 7.8; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
linux	linux kernel	cpe:2.3:o:linux:linux_kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

linux linux kernel6.10 and later · before 6.12.86
linux linux kernel6.13 and later · before 6.18.27
linux linux kernel6.19 and later · before 7.0.4

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

Linux Linux
- 6.10affected
- 848e447e000c41894ff931dc7c004fd42c8840f8 and later · before ddf96e23c366c566283fce8377928851fa7f5e81affected · git
- 848e447e000c41894ff931dc7c004fd42c8840f8 and later · before 7b436ade16cc81095d79b79f8efa3af0a4f5c5a2affected · git
- 848e447e000c41894ff931dc7c004fd42c8840f8 and later · before 7530f34ec0ca1438d45a75dcb43183a1cc92ecedaffected · git
- 848e447e000c41894ff931dc7c004fd42c8840f8 and later · before 670e8864b1a218d72f08db40d0103adf38fa1d9baffected · git
- before 6.10not affected · semver
- 6.12.86 and later · up to and including 6.12.*not affected · semver
- 6.18.27 and later · up to and including 6.18.*not affected · semver
- 7.0.4 and later · up to and including 7.0.*not affected · semver
- 7.1 and laternot affected · original_commit_for_fix

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
Debian:13	linux	before 6.12.86-1	6.12.86-1
Debian:14	linux	before 7.0.4-1	7.0.4-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

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Published before and after this one in the same product

← EarlierCVE-2026-46034May 27, 2026 · vfio/cdx: Fix NULL pointer dereference in interrupt trigger path
22Monitor
← EarlierCVE-2026-46035May 27, 2026 · mm/page_alloc: return NULL early from alloc_frozen_pages_nolock() in NMI on UP
22Monitor
Later →CVE-2026-46039May 27, 2026 · rxgk: Fix potential integer overflow in length check
39Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
Linux Linux	670e8864b1a218d72f08db40d0103adf38fa1d9b	Vendor (CNA)
Linux Linux	7530f34ec0ca1438d45a75dcb43183a1cc92eced	Vendor (CNA)
Linux Linux	7b436ade16cc81095d79b79f8efa3af0a4f5c5a2	Vendor (CNA)
Linux Linux	ddf96e23c366c566283fce8377928851fa7f5e81	Vendor (CNA)
debian:linux	6.12.86-1 · Debian:13	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Someone with local access to the system can trigger it.
A low-privileged account is enough.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Local
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-416 · Use After Free

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-secondary

Root cause

After a memory region is freed, another reference pointing to it is still used. By then, the same region may have been allocated for different data.

The bug in code

The whole CWE-416 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1free(dev->buf);
2/* ... another thread is still running ... */
3process(dev->buf);

Fixed

1lock(&dev->lock);
2free(dev->buf);
3dev->buf = NULL;
4unlock(&dev->lock);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

Fix✗ → ✓Sep 28, 2026, 10:11 PM UTC

For records you follow, these changes also arrive as notifications. →

References

git.kernel.org/stable/c/670e8864b1a218d72f08db40d0103adf38fa1d9b

Show all references (3 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records