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CVE-2026-46146 Linux CVE debrief

A vulnerability in the Linux kernel's ALSA USB audio driver could allow a malformed USB audio descriptor to trigger an endless loop. The convert_chmap_v3() function iterates through channel map descriptors using a size field (cs_desc->wLength) that was not validated, permitting a zero or malformed value to stall the kernel. The fix adds proper bounds checking to abort iteration on invalid descriptor sizes.

Vendor
Linux
Product
Unknown
CVSS
MEDIUM 5.5
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, kernel maintainers, organizations using USB audio devices on Linux workstations or embedded systems

Technical summary

The convert_chmap_v3() function in sound/usb/mixer.c processes USB audio class 3.0 channel map descriptors. The loop increment uses cs_desc->wLength without validation; a zero or overflow value causes infinite iteration. The fix introduces minimum size validation before loop progression, preventing malformed descriptors from stalling the kernel.

Defensive priority

medium

Recommended defensive actions

  • Apply kernel updates from your Linux distribution when available for CVE-2026-46146
  • Review systems with USB audio devices attached for unusual CPU consumption or kernel thread stalls
  • Monitor vendor security advisories for kernel package updates addressing this ALSA USB audio fix
  • Consider restricting physical USB port access on sensitive systems until patches are deployed

Evidence notes

The vulnerability description indicates this was resolved in the Linux kernel ALSA USB audio subsystem. Multiple stable kernel commits are referenced, suggesting backports to maintained branches. No CVSS score has been assigned by NVD (status: Awaiting Analysis). No KEV listing exists.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-46146 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-46146

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

  • CVE-2026-46146 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-46146

    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/4e0ee232ebe3df04874125d7c7f3e6c25ea5483d

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/6e7247d8f5fefeceb0bb9cc80a5388a636b219cd

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/be09b47ed8677d76962e3240c145502e2ad9f3c8

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/e0e3dcf48189603f3865f1a0b799b3b42baae96d

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/fa5b19ce69067874b1413f3c2027563bae8c2cb3

    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.