{"id":"CVE-2026-80973","revision":"a5bb4b3543154a1dbfdc30eb0b3381ed","records":[{"revision":"a5bb4b3543154a1dbfdc30eb0b3381ed","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-80973","aliases":[],"title":"ALSA: 6fire: bound the MIDI event length from the device","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: 6fire: bound the MIDI event length from the device\n\nusb6fire_comm_receiver_handler() forwards a MIDI event using a length\nbyte the device supplies, with no bound and no check that the transfer\ndelivered that many bytes:\n\n\tif (!urb->status) {\n\t\tif (rt->receiver_buffer[0] == 0x10) /* midi in event */\n\t\t\tif (midi_rt)\n\t\t\t\tmidi_rt->in_received(midi_rt,\n\t\t\t\t\t\trt->receiver_buffer + 2,\n\t\t\t\t\t\trt->receiver_buffer[1]);\n\t}\n\nreceiver_buffer is a 64-byte kzalloc() buffer (COMM_RECEIVER_BUFSIZE), so\nonly 62 bytes follow the two-byte header. receiver_buffer[1] is a u8 the\ndevice chooses, so a device that answers with 0x10 and a length of 0xFF\nmakes snd_rawmidi_receive() read 255 bytes starting two bytes into a\n64-byte object. The bytes past the buffer are handed to userspace\nthrough the rawmidi read path.\n\nurb->actual_length is not consulted either, so a short transfer leaves\nboth the type byte and the length byte at their previous values and the\nhandler acts on stale data.\n\nThe receiver URB is submitted from usb6fire_comm_init() at probe, so the\nread happens on plug with no user action; forwarding to userspace also\nneeds a MIDI input substream open, since usb6fire_midi_in_received()\nonly calls snd_rawmidi_receive() when rt->in is set.\n\nKASAN on 7.2.0-rc5 (arm64), single packet from an emulated device:\n\n BUG: KASAN: slab-out-of-bounds in snd_rawmidi_receive\n Read of size 255 at addr ffff000009f64682 by task bash/183\n __asan_memcpy\n snd_rawmidi_receive\n usb6fire_midi_in_received [snd_usb_6fire]\n usb6fire_comm_receiver_handler [snd_usb_6fire]\n Allocated by task 11:\n usb6fire_comm_init [snd_usb_6fire]\n usb6fire_chip_probe [snd_usb_6fire]\n The buggy address is located 2 bytes inside of\n allocated 64-byte region [ffff000009f64680, ffff000009f646c0)\n\nReject the event when the length exceeds the bytes that follow the\nheader, and require the transfer to have delivered the header plus that\nmany bytes. The receiver URB is submitted with a 64-byte\ntransfer_buffer_length, so a genuine device cannot deliver an event\nlonger than those 62 bytes and nothing valid is dropped.\n\nDiscovered by XBOW, triaged by Baul Lee ","state":0,"publishedAt":"2026-09-11T19:42:35.751+00:00","modifiedAt":"2026-10-19T08:45:57.889+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"unaffected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"sound/usb/6fire/comm.c\"\n ],\n \"versions\": [\n {\n \"version\": \"c6d43ba816d1cf1d125bfbfc938f2a28a87facf9\",\n \"lessThan\": \"c9204bc2ed2010e2469dbe5fce598878a37efd04\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"c6d43ba816d1cf1d125bfbfc938f2a28a87facf9\",\n \"lessThan\": \"2c590d5e1b1595d5c8fa0b72d2897423ce9985ca\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"c6d43ba816d1cf1d125bfbfc938f2a28a87facf9\",\n \"lessThan\": \"0c8a3c773823cf12abd39c480aed70e25c384630\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"c6d43ba816d1cf1d125bfbfc938f2a28a87facf9\",\n \"lessThan\": \"00e84a9ff2d43953ae261995cae94d46f4c307a6\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"c6d43ba816d1cf1d125bfbfc938f2a28a87facf9\",\n \"lessThan\": \"466e911bbbbb779bb06337e35a286e5ca7af16b3\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"c6d43ba816d1cf1d125bfbfc938f2a28a87facf9\",\n \"lessThan\": \"2a6f6fba3bd31d2e8c957fefa29156e35e5e75d5\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"c6d43ba816d1cf1d125bfbfc938f2a28a87facf9\",\n \"lessThan\": \"34816e2cfeabafb8eccf54687186ce25699e8363\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"c6d43ba816d1cf1d125bfbfc938f2a28a87facf9\",\n \"lessThan\": \"a478893b59e36cfe7d77a76b352f2db55502e879\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n }\n ]\n }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"affected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"sound/usb/6fire/comm.c\"\n ],\n \"versions\": [\n {\n \"version\": \"2.6.39\",\n \"status\": \"affected\"\n },\n {\n \"version\": \"0\",\n \"lessThan\": \"2.6.39\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.10.270\",\n \"lessThanOrEqual\": \"5.10.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.15.221\",\n \"lessThanOrEqual\": \"5.15.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.1.188\",\n \"lessThanOrEqual\": \"6.1.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.6.157\",\n \"lessThanOrEqual\": \"6.6.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.12.109\",\n \"lessThanOrEqual\": \"6.12.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.18.50\",\n \"lessThanOrEqual\": \"6.18.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.2.4\",\n \"lessThanOrEqual\": \"7.2.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.3\",\n \"lessThanOrEqual\": \"*\",\n \"status\": \"unaffected\",\n \"versionType\": \"original_commit_for_fix\"\n }\n ]\n }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/c9204bc2ed2010e2469dbe5fce598878a37efd04","https://git.kernel.org/stable/c/2c590d5e1b1595d5c8fa0b72d2897423ce9985ca","https://git.kernel.org/stable/c/0c8a3c773823cf12abd39c480aed70e25c384630","https://git.kernel.org/stable/c/00e84a9ff2d43953ae261995cae94d46f4c307a6","https://git.kernel.org/stable/c/466e911bbbbb779bb06337e35a286e5ca7af16b3","https://git.kernel.org/stable/c/2a6f6fba3bd31d2e8c957fefa29156e35e5e75d5","https://git.kernel.org/stable/c/34816e2cfeabafb8eccf54687186ce25699e8363","https://git.kernel.org/stable/c/a478893b59e36cfe7d77a76b352f2db55502e879"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-80973","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-80973","identifiers":["CVE-2026-80973"]},"retained":false,"historicalAffected":[]}],"coverage":[]}