{"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 <baul.lee@xbow.com>"}],"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"}}}}