CVE-2026-21732 | GPU DDK - libusc OOB write at ConvertSwitchToArrayLookupBP during WebGPU shader compilation

A web page that contains unusual GPU shader code is loaded into the GPU compiler process and can trigger a write out-of-bounds write crash in the GPU shader compiler library. On certain platforms, when the compiler process has system privileges this could enable further exploits on the device. An edge case using a very large value in switch statements in GPU shader code can cause a segmentation fault in the GPU shader compiler due to an out-of-bounds write access.

Published: 2026-03-20 Last update: 2026-04-21 Assigner: 367425dc-4d06-4041-9650-c2dc6aaa27ce Source: 367425dc-4d06-4041-9650-c2dc6aaa27ce
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-21732 is rated Moderate Risk (45.7/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.29%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-21732

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.05% 0.29% +0.24%
2 2026-03-26 0.02% 0.05% +0.03%
3 2026-03-21 — 0.02% —

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-21732

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.6 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 6.0 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-21732

GitHub Security Advisory for CVE-2026-21732

GHSA-2mc2-45rp-r4w4 · Severity: critical — A web page that contains unusual GPU shader code is loaded into the GPU compiler process and can...

Affected software / configurations for CVE-2026-21732

Vendor Product Version Raw CPE
imaginationtech ddk >= 24.1, <= 25.1 cpe:2.3:a:imaginationtech:ddk:*:*:*:*:*:*:*:*
imaginationtech ddk 1.17 cpe:2.3:a:imaginationtech:ddk:1.17:*:*:*:*:*:*:*
imaginationtech ddk 1.18 cpe:2.3:a:imaginationtech:ddk:1.18:*:*:*:*:*:*:*
imaginationtech ddk 23.2 cpe:2.3:a:imaginationtech:ddk:23.2:*:*:*:*:*:*:*

References for CVE-2026-21732

cvelogic Threat Intelligence