---
cve: "CVE-2026-89819"
severity: "HIGH"
cvss: 7.8
epss: "0.2%"
vendor: "Linux"
kev: false
exploited: false
published: "2026-09-16 10:30:51"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-20T16:01:11+02:00"
---

# CVE-2026-89819

> 7.8 HIGH

## Beschreibung

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

drm/amd/display: validate plane degamma LUT size for private color prop

Unlike the CRTC degamma path, which is guarded by
amdgpu_dm_verify_lut_sizes(), the per-plane degamma LUT size was never
validated before use. __set_dm_plane_degamma() passed the user-supplied
size straight into __is_lut_linear() and, for a non-linear LUT, into
__set_input_tf() -> __drm_lut_to_dc_gamma(), the latter always iterating
MAX_COLOR_LUT_ENTRIES entries regardless of the actual LUT size.

A malformed AMD_PLANE_DEGAMMA_LUT blob (e.g. a single entry) could thus
trigger a divide-by-zero in __is_lut_linear() or an out-of-bounds read in
__drm_lut_to_dc_gamma(). Reject any plane degamma LUT whose size does not
match MAX_COLOR_LUT_ENTRIES, mirroring the invariant the code already
asserts a few lines below (and which the CRTC path enforces).

The AMD_PLANE_DEGAMMA_LUT property is only exposed on builds with
AMD_PRIVATE_COLOR defined.

## CVSS-Vektor

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

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Lokal | good |
| AC Komplexität | Gering | bad |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Hoch | bad |

## Patch verfügbar (OSV)

- Kernel ≥ 6.12.110
- Kernel ≥ 6.18.51
- Kernel ≥ 7.2.5

## Referenzen

- <https://git.kernel.org/stable/c/f6f04d8ae5725bcc893bdc62e3467efd97255c5b>
- <https://git.kernel.org/stable/c/0b2615b8b54f58bbdf986dffb38cbc35214a5cc5>
- <https://git.kernel.org/stable/c/b10cc09b329245c6d95f8fa3e7f068575e3e0e9f>
- <https://git.kernel.org/stable/c/e4c3ab59021e7c146a84b6671f0d530972bd58b4>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-89819) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_