CVE-2026-68206

Received Received - Intake

Linux Kernel HEVC Active Reference Count Validation

Publication date: 2026-08-10

Last updated on: 2026-08-19

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: media: v4l2-ctrls: validate HEVC active reference counts HEVC slice parameters are shared stateless V4L2 controls, but the common validation path does not verify the active L0/L1 reference counts before driver-specific code consumes them. The original report came from Cedrus, but the active count bounds are not Cedrus-specific. Validate them in the common HEVC slice control path so stateless HEVC drivers get the same basic guarantees as soon as the control is queued. Do not reject ref_idx_l0/ref_idx_l1 entries here. Existing userspace may use out-of-range sentinel values such as 0xff for missing references, and some hardware can use that information for concealment. Keep this common check limited to the active reference counts.

CVSS Scores

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Meta Information

Published

2026-08-10

Last Modified

2026-08-19

Generated

2026-08-30

AI Q&A

2026-08-10

EPSS Evaluated

2026-08-29

NVD

CVE-2026-68206

EUVD

EUVD-2026-55307

Affected Vendors & Products

Vendor	Product	Version / Range
linux	linux_kernel	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This vulnerability in the Linux kernel involves insufficient validation of HEVC (High Efficiency Video Coding) active reference counts in the V4L2 (Video4Linux2) controls. HEVC slice parameters are shared stateless controls, but the common validation path does not check the active L0/L1 reference counts before driver-specific code uses them. This could lead to improper handling of reference counts by stateless HEVC drivers.

Detection Guidance

This vulnerability is specific to the Linux kernel's media subsystem and involves HEVC video decoding. Detection requires checking kernel logs for related errors or kernel crashes during HEVC video processing. Commands like dmesg | grep -i HEVC or journalctl -k | grep -i HEVC may help identify issues.

Impact Analysis

This vulnerability may allow an attacker to cause a denial of service or potentially execute arbitrary code in the kernel if exploited. It could lead to system crashes, instability, or unauthorized access depending on the driver and hardware configuration. Users running affected Linux kernel versions with HEVC video processing are at risk.

Compliance Impact

This vulnerability does not directly affect compliance with GDPR, HIPAA, or similar standards. It is a low-level kernel media driver issue that could lead to memory corruption or undefined behavior in HEVC video processing, but no evidence suggests it impacts data protection or privacy compliance requirements.

Mitigation Strategies

Update the Linux kernel to the latest stable version that includes the fix for this vulnerability. If updating is not immediately possible, avoid processing HEVC video streams until the kernel is updated to prevent potential exploitation.

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