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Response snapshot Nov 6, 2026, 19:41 UTC

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VulnerabilityCVE-2026-46309

Linux kernel: drm/xe/uapi: Reject coh_none PAT index for CPU cached memory in madvise

In the Linux kernel, the following vulnerability has been resolved: drm/xe/uapi: Reject coh_none PAT index for CPU cached memory in madvise Add validation in xe_vm_madvise_ioctl() to reject PAT indices with XE_COH_NONE coherency mode when applied to CPU cached memory.

At a glance

Exploited
Not known
Severity
7.0 High (CVSS 3.1)
Chance of exploitation
0.1% in the next 30 days
Sources
1 source

What to do

Check the vendor advisory for affected versions and fixes.

Read NVD CVE-2026-46309 (opens a new tab)

What happened

In the Linux kernel, the following vulnerability has been resolved:

drm/xe/uapi: Reject coh_none PAT index for CPU cached memory in madvise

Add validation in xe_vm_madvise_ioctl() to reject PAT indices with XE_COH_NONE coherency mode when applied to CPU cached memory.

Using coh_none with CPU cached buffers is a security issue. When the kernel clears pages before reallocation, the clear operation stays in CPU cache (dirty). GPU with coh_none can bypass CPU caches and read stale sensitive data directly from DRAM, potentially leaking data from previously freed pages of other processes.

Continue reading

This aligns with the existing validation in vm_bind path (xe_vm_bind_ioctl_validate_bo).

v2(Matthew brost) - Add fixes - Move one debug print to better place

v3(Matthew Auld) - Should be drm/xe/uapi - More Cc

v4(Shuicheng Lin) - Fix kmem leak issues by the way

v5 - Remove kmem leak because it has been merged by another patch

v6 - Remove the fix which is not related to current fix

v7 - No change

v8 - Rebase

v9 - Limit the restrictions to iGPU

v10 - No change

(cherry picked from commit 016ccdb674b8c899940b3944952c96a6a490d10a)

Scores and how they were measured

CVSS base severity

7.0

Version 3.1As of

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

Measurement source (opens a new tab)

How bad it is if exploited. Not a prediction of exploitation or proof you are exposed.

EPSS probability

0.1%

Scored Percentile 2.2%

Model and measurement source (opens a new tab)

A model's estimate of exploitation in the next 30 days, not certainty or your own risk.

Related technology

Sources

  1. Primary source

    NVD CVE-2026-46309 (opens a new tab)

    NVD record: description, CVSS (the CNA score is preferred), affected products, and publication date. Not evidence of exploitation.

    Published Checked

  2. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

  3. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

  4. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

  5. Primary source

    FIRST measured EPSS score (opens a new tab)

    Measured EPSS probability and percentile for CVE-2026-46309, scored 2026-11-06. This is a model estimate, not proof of exposure.

    Published Checked

Cite this record

For factual claims, cite the primary sources above; cite KEVWire for its compilation, dates, and classifications.

APA

KEVWire. (2026, November 6). Linux kernel: drm/xe/uapi: Reject coh_none PAT index for CPU cached memory in madvise (CVE-2026-46309). https://kevwire.com/record/CVE-2026-46309

MLA

"Linux kernel: drm/xe/uapi: Reject coh_none PAT index for CPU cached memory in madvise (CVE-2026-46309)." KEVWire, 6 Nov. 2026, kevwire.com/record/CVE-2026-46309.

Chicago

KEVWire. "Linux kernel: drm/xe/uapi: Reject coh_none PAT index for CPU cached memory in madvise (CVE-2026-46309)." Last modified November 6, 2026. https://kevwire.com/record/CVE-2026-46309.

Evidence summary (plain text)

Linux kernel: drm/xe/uapi: Reject coh_none PAT index for CPU cached memory in madvise (Jun 8, 2026).
In the Linux kernel, the following vulnerability has been resolved:

drm/xe/uapi: Reject coh_none PAT index for CPU cached memory in madvise

Add validation in xe_vm_madvise_ioctl() to reject PAT indices with
XE_COH_NONE coherency mode when applied to CPU cached memory.

Using coh_none with CPU cached buffers is a security issue. When the
kernel clears pages before reallocation, the clear operation stays in
CPU cache (dirty). GPU with coh_none can bypass CPU caches and read
stale sensitive data directly from DRAM, potentially leaking data from
previously freed pages of other processes.
CVSS 7.0 (version 3.1; evidence as of Nov 6, 2026; https://nvd.nist.gov/vuln/detail/CVE-2026-46309).
EPSS 0.1% for the following 30 days, scored Nov 6, 2026 (https://api.first.org/data/v1/epss?cve=CVE-2026-46309&date=2026-11-06).
Sources:
NVD CVE-2026-46309: https://nvd.nist.gov/vuln/detail/CVE-2026-46309
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-11-06T17:06:05.906Z&lastModEndDate=2026-11-06T18:35:59.598Z&resultsPerPage=500&startIndex=0
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-11-06T16:31:13.932Z&lastModEndDate=2026-11-06T18:05:57.615Z&resultsPerPage=500&startIndex=0
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-11-06T15:50:58.372Z&lastModEndDate=2026-11-06T17:30:57.197Z&resultsPerPage=500&startIndex=0
FIRST measured EPSS score: https://api.first.org/data/v1/epss?cve=CVE-2026-46309&date=2026-11-06
Record ID: CVE-2026-46309.
Record origin: Ingested record.
AI evidence: Not assessed.
Known exploitation: Not assessed.
Zero-day status: Not assessed. KEV membership alone does not establish zero-day status.
About this data

This record was ingested from a data source. Retrieved: Nov 6, 2026, 19:36 UTC. Ingestion is not an independent editorial investigation.

NVD status: Analyzed. Publication in the NVD is not evidence of exploitation.

A CISA KEV listing documents known exploitation, not necessarily a zero-day; absence from the catalog does not prove a vulnerability has never been exploited.

Technology tags indicate possible relevance, not verified exposure. Confirm the affected product, version, and configuration against your own inventory; KEVWire does not scan your systems.

A personal reading checklist on this device, not verified remediation.

Record JSON

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Record details

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