# CVE-2026-72358: drm/xe/pt: prevent invalid cursor access for purged BOs

> A missing check for purged buffer objects in the Intel Xe GPU driver causes invalid cursor access, leading to kernel warnings and potential denial of service.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 15 Aug 2026
- **Updated:** 17 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-72358, GHSA-p58g-v37m-9wmc, UBUNTU-CVE-2026-72358

## What is CVE-2026-72358?

CVE-2026-72358 is a high-severity vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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

drm/xe/pt: prevent invalid cursor access for purged BOs

During a page table walk for binding, xe_pt_stage_bind() explicitly
skips initializing the xe_res_cursor for purged BOs, treating them
similarly to NULL VMAs by only setting the cursor size.

However, xe_pt_hugepte_possible() and xe_pt_scan_64K() did not check
if the BO was purged before attempting to walk the cursor using
xe_res_dma() and xe_res_next(). Because the cursor was left
uninitialized for purged BOs, this falls through and triggers
warnings like:

  WARNING: drivers/gpu/drm/xe/xe_res_cursor.h:274 at xe_res_next

Fix this by explicitly checking if the BO is purged in both
xe_pt_hugepte_possible() and xe_pt_scan_64K(), returning early just
as we do for NULL VMAs, avoiding the invalid cursor accesses entirely.

As a precaution, also zero-initialize the cursor in xe_pt_stage_bind()
to ensure we don't pass garbage data into the page table walkers
if we ever hit a similar edge case in the future.

(cherry picked from commit 4c7b9c6ece32440e5a435a92076d049450cd2d2e)

## Which versions are affected by CVE-2026-72358?


## How do I fix CVE-2026-72358?

Apply the vendor's patch.

## Is CVE-2026-72358 being exploited?

There is no known exploitation of CVE-2026-72358 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-72358 and fix it if it is affected.

What it is: CVE-2026-72358 is a high-severity vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-72358 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-72358/ (Markdown: https://insights.sbomify.com/CVE-2026-72358/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-72358
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-72358
- OSV: https://osv.dev/vulnerability/CVE-2026-72358

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-72358/
Summaries are generated and may contain mistakes; the official description above is the record.