{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-74682", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.925Z", "datePublished": "2026-08-22T15:32:49.527Z", "dateUpdated": "2026-08-22T15:32:49.527Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-22T15:32:49.527Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: usb-audio: fix OOB write on Type II inbound URBs\n\ndata_ep_set_params() sizes each URB transfer buffer before it adds the\nFormat Type II transfer delimiter:\n\n\tu->packets = urb_packs;\n\tu->buffer_size = maxsize * u->packets;\n\n\tif (fmt->fmt_type == UAC_FORMAT_TYPE_II)\n\t\tu->packets++; /* for transfer delimiter */\n\tu->urb = usb_alloc_urb(u->packets, GFP_KERNEL);\n\nbuffer_size is computed from the pre-increment packet count and never\nrecomputed, so for a Type II endpoint the buffer is one packet short of\nthe packet count the URB is built with.\n\nprepare_inbound_urb() then lays out one iso frame per packet and never\nconsults buffer_size:\n\n\toffs = 0;\n\tfor (i = 0; i < urb_ctx->packets; i++) {\n\t\turb->iso_frame_desc[i].offset = offs;\n\t\turb->iso_frame_desc[i].length = ep->curpacksize;\n\t\toffs += ep->curpacksize;\n\t}\n\n\turb->transfer_buffer_length = offs;\n\turb->number_of_packets = urb_ctx->packets;\n\nThe last descriptor therefore points one packet past the end of the\ntransfer buffer, where the host controller writes device data on every\ninbound transfer. prepare_silent_urb() and prepare_playback_urb() bound\ntheir fill loops by ctx->buffer_size, so only capture is affected.\n\nfmt_type comes from the device's audio streaming descriptors, so any\ndevice advertising a Type II capture format hits this once userspace sets\nhw_params on the stream.\n\nKASAN on 7.2.0-rc5 (arm64) with a dummy_hcd/raw-gadget device, one report\nper inbound transfer:\n\n BUG: KASAN: slab-out-of-bounds in dummy_timer\n Write of size 64 at addr ffff0000186171c0 by task cons02/166\n __asan_memcpy\n dummy_timer\n hrtimer_run_softirq\n Allocated by task 166:\n usb_alloc_coherent\n snd_usb_endpoint_set_params\n The buggy address is located 0 bytes to the right of\n allocated 64-byte region [ffff000018617180, ffff0000186171c0)\n\nCompute buffer_size after the delimiter packet has been accounted for,\nand bound the fill loop by buffer_size, as prepare_silent_urb() already\ndoes on the outbound side. This grows every Type II URB allocation by\none maxsize packet.\n\nDiscovered by XBOW, triaged by Baul Lee " } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "sound/usb/endpoint.c" ], "versions": [ { "version": "8fdff6a319e7dac757c558bd283dc4577e68cde7", "lessThan": "6af5f29af7711233ae68d3b25c15d67478468900", "status": "affected", "versionType": "git" }, { "version": "8fdff6a319e7dac757c558bd283dc4577e68cde7", "lessThan": "f1fbb50b99311b35c2e85cc70341d62082dca4b5", "status": "affected", "versionType": "git" }, { "version": "8fdff6a319e7dac757c558bd283dc4577e68cde7", "lessThan": "137bf034740e5a2734794908d0aff1e0bd7cee6e", "status": "affected", "versionType": "git" }, { "version": "8fdff6a319e7dac757c558bd283dc4577e68cde7", "lessThan": "6607f85242577f33d4540a0d1f4a6137f5367058", "status": "affected", "versionType": "git" }, { "version": "8fdff6a319e7dac757c558bd283dc4577e68cde7", "lessThan": "ca22c94bdfc22c564ca2e11c87ba4d17ebeaaa9a", "status": "affected", "versionType": "git" }, { "version": "8fdff6a319e7dac757c558bd283dc4577e68cde7", "lessThan": "0a235379825e1a6194e43861ee6658e5fc35686d", "status": "affected", "versionType": "git" }, { "version": "8fdff6a319e7dac757c558bd283dc4577e68cde7", "lessThan": "d3ed4e6321bb453757044cb9e5ecb30a33f04903", "status": "affected", "versionType": "git" }, { "version": "8fdff6a319e7dac757c558bd283dc4577e68cde7", "lessThan": "69ee44e1a23be62318189dc4b37fa4ad94053269", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "sound/usb/endpoint.c" ], "versions": [ { "version": "3.5", "status": "affected" }, { "version": "0", "lessThan": "3.5", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.265", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.216", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.183", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.152", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.104", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.45", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.9", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "5.10.265" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "5.15.216" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "6.1.183" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "6.6.152" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "6.12.104" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "6.18.45" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "7.1.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/6af5f29af7711233ae68d3b25c15d67478468900" }, { "url": "https://git.kernel.org/stable/c/f1fbb50b99311b35c2e85cc70341d62082dca4b5" }, { "url": "https://git.kernel.org/stable/c/137bf034740e5a2734794908d0aff1e0bd7cee6e" }, { "url": "https://git.kernel.org/stable/c/6607f85242577f33d4540a0d1f4a6137f5367058" }, { "url": "https://git.kernel.org/stable/c/ca22c94bdfc22c564ca2e11c87ba4d17ebeaaa9a" }, { "url": "https://git.kernel.org/stable/c/0a235379825e1a6194e43861ee6658e5fc35686d" }, { "url": "https://git.kernel.org/stable/c/d3ed4e6321bb453757044cb9e5ecb30a33f04903" }, { "url": "https://git.kernel.org/stable/c/69ee44e1a23be62318189dc4b37fa4ad94053269" } ], "title": "ALSA: usb-audio: fix OOB write on Type II inbound URBs", "x_generator": { "engine": "bippy-1.2.0" } } } }