# CVE-2026-64546: drm/edid: fix OOB read in drm_parse_tiled_block()

> A crafted EDID triggers an out-of-bounds read in the Linux kernel's DRM subsystem, potentially leaking memory or causing a crash.

- **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/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:** 27 Jul 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-94067, BELL-CVE-2026-64546, DEBIAN-CVE-2026-64546, GHSA-7h2w-78jh-69gr, ROOT-OS-DEBIAN-12-CVE-2026-64546, UBUNTU-CVE-2026-64546

## What is CVE-2026-64546?

CVE-2026-64546 is a high-severity memory corruption vulnerability in Linux, published on 27 Jul 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/edid: fix OOB read in drm_parse_tiled_block()

drm_parse_tiled_block() casts the DisplayID block to a
struct displayid_tiled_block and reads the full fixed layout up to
tile->topology_id[7] without checking block->num_bytes. The DisplayID
iterator only validates the declared payload length, so a crafted EDID
can advertise a tiled-display block (tag DATA_BLOCK_TILED_DISPLAY, or
DATA_BLOCK_2_TILED_DISPLAY_TOPOLOGY for v2.0) with a small num_bytes at
the end of a DisplayID extension. The read then runs past the end of the
exact-sized kmemdup()'d EDID allocation, a heap out-of-bounds read.

Reject blocks shorter than the spec's 22-byte tiled payload before
reading the fixed struct, as drm_parse_vesa_mso_data() already does.

  BUG: KASAN: slab-out-of-bounds in drm_edid_connector_update
  Read of size 2 at addr ffff888010077700 by task exploit/147
   dump_stack_lvl (lib/dump_stack.c:94 ...)
   print_report (mm/kasan/report.c:378 ...)
   kasan_report (mm/kasan/report.c:595)
   drm_edid_connector_update (drivers/gpu/drm/drm_edid.c:7581)
   bochs_connector_helper_get_modes (drivers/gpu/drm/tiny/bochs.c:574)
   drm_helper_probe_single_connector_modes (drivers/gpu/drm/drm_probe_helper.c:426)
   status_store (drivers/gpu/drm/drm_sysfs.c:219)
   ...
   vfs_write (fs/read_write.c:595 fs/read_write.c:688)
   ksys_write (fs/read_write.c:740)

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-64546?


## How do I fix CVE-2026-64546?

Apply the vendor's patch.

## Is CVE-2026-64546 being exploited?

There is no known exploitation of CVE-2026-64546 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64546 and fix it if it is affected.

What it is: CVE-2026-64546 is a high-severity memory corruption vulnerability in Linux, published on 27 Jul 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-2026-64546 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-2026-64546/ (Markdown: https://insights.sbomify.com/CVE-2026-64546/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64546
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64546
- OSV: https://osv.dev/vulnerability/CVE-2026-64546

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64546/
Summaries are generated and may contain mistakes; the official description above is the record.