# CVE-2026-43436: ALSA: usb-audio: Check endpoint numbers at parsing Scarlett2 mixer interfaces

Status: published. Published: 2026-05-08. Updated: 2026-11-06.

In the Linux kernel, the following vulnerability has been resolved:

ALSA: usb-audio: Check endpoint numbers at parsing Scarlett2 mixer interfaces

The Scarlett2 mixer quirk in USB-audio driver may hit a NULL
dereference when a malformed USB descriptor is passed, since it
assumes the presence of an endpoint in the parsed interface in
scarlett2_find_fc_interface(), as reported by fuzzer.

For avoiding the NULL dereference, just add the sanity check of
bNumEndpoints and skip the invalid interface.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Linux / Linux: ≥ 6c0a2078134aba6a77291554035304df9e16b85c; < b014cc945baba75816cda0cf8934be87c9ed4947 (affected, git); ≥ 6c0a2078134aba6a77291554035304df9e16b85c; < c5c5a6c53cf3b658f1d4512dfa61f3cd25bc34ba (affected, git); ≥ 6c0a2078134aba6a77291554035304df9e16b85c; < b267255c15d2a5b90c4e926146aa155e5161e264 (affected, git); ≥ 6c0a2078134aba6a77291554035304df9e16b85c; < 3d542cf3c4c854cdf5d58049771f68926b9eb2b9 (affected, git); ≥ 6c0a2078134aba6a77291554035304df9e16b85c; < 3d4f23885e4b90347c9a1d779af6e79a99b5172a (affected, git); ≥ 6c0a2078134aba6a77291554035304df9e16b85c; < df1d8abf36ca3681c21a6809eaa9a1e01ef897a6 (affected, git). Source: CNA: Linux
- Linux / Linux: 5.14 (affected); ≥ 0; < 5.14 (unaffected, semver); ≥ 6.1.167; ≤ 6.1.* (unaffected, semver); ≥ 6.6.130; ≤ 6.6.* (unaffected, semver); ≥ 6.12.78; ≤ 6.12.* (unaffected, semver); ≥ 6.18.19; ≤ 6.18.* (unaffected, semver); ≥ 6.19.9; ≤ 6.19.* (unaffected, semver); ≥ 7.0; ≤ * (unaffected, original_commit_for_fix). Source: CNA: Linux

## Severity and prioritization

- CISA KEV: No listing in collected sources

- EPSS: 0.12% as of 2026-11-06; percentile 2.03%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: Not reported

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://git.kernel.org/stable/c/b014cc945baba75816cda0cf8934be87c9ed4947 (CNA: Linux)

- https://git.kernel.org/stable/c/c5c5a6c53cf3b658f1d4512dfa61f3cd25bc34ba (CNA: Linux)

- https://git.kernel.org/stable/c/b267255c15d2a5b90c4e926146aa155e5161e264 (CNA: Linux)

- https://git.kernel.org/stable/c/3d542cf3c4c854cdf5d58049771f68926b9eb2b9 (CNA: Linux)

- https://git.kernel.org/stable/c/3d4f23885e4b90347c9a1d779af6e79a99b5172a (CNA: Linux)

- https://git.kernel.org/stable/c/df1d8abf36ca3681c21a6809eaa9a1e01ef897a6 (CNA: Linux)

## Provenance

- CNA: Linux: https://www.cve.org/CVERecord?id=CVE-2026-43436; retrieved 2026-11-06; source updated 2026-11-06

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-43436; retrieved 2026-11-06; source updated Not reported

Revision: 6b75935e584fc08ba8a7f2d14009e53bc1e2bc07f13fdd7e7a61e36aa441c7b3

Canonical: https://y2.dev/cve/CVE-2026-43436

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.