CVE-2026-46309 Details
Description
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. 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)
A vulnerability exists in the Linux kernel's DRM/xe user API, specifically in the memory advice (madvise) handling. The issue arises from the acceptance of certain memory coherency modes that can lead to the leakage of sensitive data. When the kernel clears memory pages before they are reallocated, the cleared data can remain in the CPU cache. A GPU operating under the 'coh_none' mode can bypass the CPU cache and access this stale data directly from the DRAM. This could potentially expose information from previously freed memory pages of other processes. The vulnerability affects Linux kernel versions 6.18 and later.
Users can upgrade to the latest version of the Linux kernel, where this vulnerability has been addressed. Instructions for downloading the latest kernel version can be found on the official Linux kernel website.
Metrics
CVSS 4.0 Severity and Vector Strings:
No CVSS 4.0 data is available for this CVE.
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
No SSVC data is available for this CVE.
References to Advisories, Solutions, and Tools
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| URL | Source(s) | Tag(s) |
|---|---|---|
| https://access.redhat.com/security/cve/CVE-2026-46309 | redhat-SADP | Third Party Advisory |
| https://bugzilla.redhat.com/show_bug.cgi?id=2486468 | redhat-SADP | Third Party Advisory |
| https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46309.json | redhat-SADP | Third Party Advisory |
| https://git.kernel.org/stable/c/4e5591c2fc1b30f4ea5e2eab4c3a695acc404e39 | kernel.org | Patch |
| https://git.kernel.org/stable/c/87f9b1528e1ffc1da3615d552c9a06aba5e20b00 | kernel.org | Patch |
| https://git.kernel.org/stable/c/fea04cf6f2345bc50f15b6638906c35962b89424 | kernel.org | Patch |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-401 | Missing Release of Memory after Effective Lifetime | [email protected] |
| CWE-524 | Use of Cache Containing Sensitive Information | redhat-SADP |
Affected Products
| Product | Versions |
|---|---|
| linux linux kernel | >= 6.18, < 6.18.32 >= 6.19, < 7.0.9 7.1 rc1 |
CPE
Remediation
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Change History
6 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jul 23, 2026 | CVE Translated | [email protected] |
| Jul 15, 2026 | CVE Modified | redhat-SADP |
| Jul 8, 2026 | Initial Analysis | [email protected] |
| Jun 30, 2026 | CVE Modified | redhat-SADP |
| Jun 17, 2026 | CVE Modified | kernel.org |
| Jun 8, 2026 | New CVE Received | kernel.org |