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CVE-2026-46199 Linux CVE debrief

A bounds-checking vulnerability in the Linux kernel's AMDGPU VCN4 (Video Core Next 4) driver could allow out-of-bounds (OOB) memory reads when parsing decoder messages. The flaw exists because the driver previously failed to validate buffer object (BO) bounds before accessing message data. An attacker with local access could potentially exploit this to read kernel memory, leading to information disclosure or system instability. The vulnerability affects AMD GPU systems utilizing the VCN4 hardware block for video decode operations. The fix adds explicit bounds checks against the end of the BO on all message access paths.

Vendor
Linux
Product
Unknown
CVSS
HIGH 7.1
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-28
Original CVE updated
2026-05-30
Advisory published
2026-05-28
Advisory updated
2026-05-30

Who should care

Linux system administrators running kernels with AMD GPU support, particularly those enabling video decode functionality for untrusted content; security teams tracking kernel driver vulnerabilities; organizations with VDI or media processing workloads on AMD GPU hardware

Technical summary

The AMDGPU kernel driver's VCN4 (Video Core Next 4) video decode component contained a missing bounds validation vulnerability. When parsing decoder messages, the driver accessed message data without first verifying that offsets remained within the allocated buffer object (BO) boundaries. This could result in out-of-bounds reads from kernel memory. The resolution adds explicit bounds checks against the BO end for all message access operations. The fix has been backported to multiple stable kernel branches as evidenced by five referenced commits.

Defensive priority

medium

Recommended defensive actions

  • Apply kernel updates from your Linux distribution that include the drm/amdgpu/vcn4 bounds-checking fix for CVE-2026-46199
  • Verify kernel version includes commits addressing VCN4 decoder message parsing (check stable kernel changelogs for relevant backports)
  • On systems with AMD GPUs using VCN4 video decode, prioritize patching if untrusted users can access video decode functionality
  • Monitor NVD for CVSS scoring updates as analysis completes
  • Review system logs for any anomalous AMDGPU VCN4-related errors that may indicate exploitation attempts

Evidence notes

The CVE description confirms this is a resolved Linux kernel vulnerability in drm/amdgpu/vcn4. The fix involves adding bounds checks when parsing decoder messages to prevent OOB reads. Multiple stable kernel branch commits are referenced, indicating backports to supported kernel versions. The vulnerability is classified as 'Awaiting Analysis' in NVD with no CVSS score assigned at time of disclosure.

Official resources

2026-05-28