{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98265","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-25T10:25:14.333Z","datePublished":"2026-10-06T08:45:28.438Z","dateUpdated":"2026-10-06T08:45:28.438Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-10-06T08:45:28.438Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: usb-audio: Clamp implicit feedback packet count to URB capacity\n\ndata_ep_set_params() allocates each data URB for exactly u->packets\nisochronous frames, so urb->iso_frame_desc[] has u->packets slots and\nctx->packets is the driver's only record of that limit. For an implicit\nfeedback sink, snd_usb_queue_pending_output_urbs() overwrites it with the\nsync source's packet count, which is calculated independently from the\ncapture endpoint's parameters. When that count is larger,\nprepare_playback_urb() and prepare_silent_urb() can write\niso_frame_desc[] past the allocation; their existing bounds limit payload\nbytes, not the descriptor index.\n\nThe reproducer uses a high-speed UAC2 device declaring bInterval 1 for\nimplicit feedback capture (8 packets) and bInterval 4 for playback\n(1 packet). On the first capture completion after the stream starts, it\naccesses seven descriptors spanning 112 bytes beyond the one-packet URB:\n\n  BUG: KASAN: slab-out-of-bounds in prepare_playback_urb (sound/usb/pcm.c:1560)\n  Write of size 4 at addr ffff88801e696ad0 by task vhci_rx/178\n   prepare_playback_urb (sound/usb/pcm.c:1560)\n   prepare_outbound_urb (sound/usb/endpoint.c:340)\n   snd_usb_queue_pending_output_urbs (sound/usb/endpoint.c:501)\n   snd_complete_urb (sound/usb/endpoint.c:1834)\n   __usb_hcd_giveback_urb (drivers/usb/core/hcd.c:1657)\n   usb_hcd_giveback_urb (drivers/usb/core/hcd.c:1741)\n   vhci_rx_loop (drivers/usb/usbip/vhci_rx.c:107)\n   kthread (kernel/kthread.c:436)\n  The buggy address belongs to the object at ffff88801e696a00\n   which belongs to the cache kmalloc-256 of size 256\n  The buggy address is located 0 bytes to the right of\n   allocated 208-byte region [ffff88801e696a00, ffff88801e696ad0)\n\nRecord the allocated packet count per endpoint and clamp both the adopted\ncount and the packet-size copy to it. Fold the Format Type II delimiter\ninto urb_packs before the allocation loop so the recorded limit matches\nevery URB."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["sound/usb/card.h","sound/usb/endpoint.c"],"versions":[{"version":"32a1f64f8ff6e2c5391f5964baec697bce25b83c","lessThan":"ad279ba0dc1781229f5b52f58d38d56960400e06","status":"affected","versionType":"git"},{"version":"e949fd266cfa1dcca7caa3faa698578c4ffd26d6","lessThan":"79c55a7b5d71cf2a6bbd4bd7698e1b10b70f813a","status":"affected","versionType":"git"},{"version":"cf044e44190234a41a788de1cdbb6c21f4a52e1e","lessThan":"ab77e3f453c5f2499c08d6e8e218501d25bab39e","status":"affected","versionType":"git"},{"version":"cf044e44190234a41a788de1cdbb6c21f4a52e1e","lessThan":"76a986c980bb502c7688d605ac7a67fd257a9a1b","status":"affected","versionType":"git"},{"version":"df75696e70c88b22ed1d8c9d515993a858c58fd0","status":"affected","versionType":"git"},{"version":"3a74f6b46c01d9a816378cd83c327a59f61475ec","status":"affected","versionType":"git"},{"version":"c26bde6301f20d9aafbfb7c2459a88c6a6ec178f","status":"affected","versionType":"git"},{"version":"f6fbdf797e016fbf968dd54301026b182175985a","status":"affected","versionType":"git"},{"version":"6.12.75","lessThan":"6.12.112","status":"affected","versionType":"semver"},{"version":"6.18.16","lessThan":"6.18.54","status":"affected","versionType":"semver"},{"version":"5.15.202","lessThan":"5.16","status":"affected","versionType":"semver"},{"version":"6.1.165","lessThan":"6.2","status":"affected","versionType":"semver"},{"version":"6.6.128","lessThan":"6.7","status":"affected","versionType":"semver"},{"version":"6.19.6","lessThan":"6.20","status":"affected","versionType":"semver"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["sound/usb/card.h","sound/usb/endpoint.c"],"versions":[{"version":"7.0","status":"affected"},{"version":"0","lessThan":"7.0","status":"unaffected","versionType":"semver"},{"version":"6.12.112","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.54","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.8","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc4","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":"6.12.75","versionEndExcluding":"6.12.112"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18.16","versionEndExcluding":"6.18.54"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.0","versionEndExcluding":"7.2.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.0","versionEndExcluding":"7.3-rc4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15.202"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1.165"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6.128"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19.6"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/ad279ba0dc1781229f5b52f58d38d56960400e06"},{"url":"https://git.kernel.org/stable/c/79c55a7b5d71cf2a6bbd4bd7698e1b10b70f813a"},{"url":"https://git.kernel.org/stable/c/ab77e3f453c5f2499c08d6e8e218501d25bab39e"},{"url":"https://git.kernel.org/stable/c/76a986c980bb502c7688d605ac7a67fd257a9a1b"}],"title":"ALSA: usb-audio: Clamp implicit feedback packet count to URB capacity","x_generator":{"engine":"bippy-1.2.0"}}}}