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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
2026-06-10
Advisory published
2026-05-28
Advisory updated
2026-06-10

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.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-46199 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-46199

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-46199 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-46199

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/0a78f2bac1424deb7c9d5e09c6b8e849d8e8b648

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/3c817a60b09eaab926e475088e750936efcc95ae

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/63b51e8a9d54317d31cc3856c1e12407070d5fc2

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/7688143ca62edeecacb3ba0a2cea129dbd262a18

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/c72a8b4dc6d598e3831ef3abd9c6527dfbf4810e

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.