{"api_version":"1","generated_at":"2026-10-07T01:52:45+00:00","cve":"CVE-2026-98265","urls":{"html":"https://cve.report/CVE-2026-98265","api":"https://cve.report/api/cve/CVE-2026-98265.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98265","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98265"},"summary":{"title":"ALSA: usb-audio: Clamp implicit feedback packet count to URB capacity","description":"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.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-10-06 09:18:15","updated_at":"2026-10-06 09:18:15"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/79c55a7b5d71cf2a6bbd4bd7698e1b10b70f813a","name":"https://git.kernel.org/stable/c/79c55a7b5d71cf2a6bbd4bd7698e1b10b70f813a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/76a986c980bb502c7688d605ac7a67fd257a9a1b","name":"https://git.kernel.org/stable/c/76a986c980bb502c7688d605ac7a67fd257a9a1b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/ad279ba0dc1781229f5b52f58d38d56960400e06","name":"https://git.kernel.org/stable/c/ad279ba0dc1781229f5b52f58d38d56960400e06","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/ab77e3f453c5f2499c08d6e8e218501d25bab39e","name":"https://git.kernel.org/stable/c/ab77e3f453c5f2499c08d6e8e218501d25bab39e","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98265","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98265","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 32a1f64f8ff6e2c5391f5964baec697bce25b83c ad279ba0dc1781229f5b52f58d38d56960400e06 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e949fd266cfa1dcca7caa3faa698578c4ffd26d6 79c55a7b5d71cf2a6bbd4bd7698e1b10b70f813a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected cf044e44190234a41a788de1cdbb6c21f4a52e1e ab77e3f453c5f2499c08d6e8e218501d25bab39e git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected cf044e44190234a41a788de1cdbb6c21f4a52e1e 76a986c980bb502c7688d605ac7a67fd257a9a1b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected df75696e70c88b22ed1d8c9d515993a858c58fd0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3a74f6b46c01d9a816378cd83c327a59f61475ec git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected c26bde6301f20d9aafbfb7c2459a88c6a6ec178f git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f6fbdf797e016fbf968dd54301026b182175985a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.12.75 6.12.112 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.18.16 6.18.54 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.15.202 5.16 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.1.165 6.2 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.6.128 6.7 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.19.6 6.20 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7.0","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.112 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.54 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.8 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc4 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"98265","cve":"CVE-2026-98265","epss":"0.001750000","percentile":"0.063790000","score_date":"2026-10-06","updated_at":"2026-10-07 00:14:55"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["sound/usb/card.h","sound/usb/endpoint.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"ad279ba0dc1781229f5b52f58d38d56960400e06","status":"affected","version":"32a1f64f8ff6e2c5391f5964baec697bce25b83c","versionType":"git"},{"lessThan":"79c55a7b5d71cf2a6bbd4bd7698e1b10b70f813a","status":"affected","version":"e949fd266cfa1dcca7caa3faa698578c4ffd26d6","versionType":"git"},{"lessThan":"ab77e3f453c5f2499c08d6e8e218501d25bab39e","status":"affected","version":"cf044e44190234a41a788de1cdbb6c21f4a52e1e","versionType":"git"},{"lessThan":"76a986c980bb502c7688d605ac7a67fd257a9a1b","status":"affected","version":"cf044e44190234a41a788de1cdbb6c21f4a52e1e","versionType":"git"},{"status":"affected","version":"df75696e70c88b22ed1d8c9d515993a858c58fd0","versionType":"git"},{"status":"affected","version":"3a74f6b46c01d9a816378cd83c327a59f61475ec","versionType":"git"},{"status":"affected","version":"c26bde6301f20d9aafbfb7c2459a88c6a6ec178f","versionType":"git"},{"status":"affected","version":"f6fbdf797e016fbf968dd54301026b182175985a","versionType":"git"},{"lessThan":"6.12.112","status":"affected","version":"6.12.75","versionType":"semver"},{"lessThan":"6.18.54","status":"affected","version":"6.18.16","versionType":"semver"},{"lessThan":"5.16","status":"affected","version":"5.15.202","versionType":"semver"},{"lessThan":"6.2","status":"affected","version":"6.1.165","versionType":"semver"},{"lessThan":"6.7","status":"affected","version":"6.6.128","versionType":"semver"},{"lessThan":"6.20","status":"affected","version":"6.19.6","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["sound/usb/card.h","sound/usb/endpoint.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"7.0"},{"lessThan":"7.0","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.112","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.54","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.8","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc4","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.112","versionStartIncluding":"6.12.75","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.54","versionStartIncluding":"6.18.16","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.8","versionStartIncluding":"7.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc4","versionStartIncluding":"7.0","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","vulnerable":true}],"negate":false,"operator":"OR"}]}],"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."}],"providerMetadata":{"dateUpdated":"2026-10-06T08:45:28.438Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"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"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98265","datePublished":"2026-10-06T08:45:28.438Z","dateReserved":"2026-09-25T10:25:14.333Z","dateUpdated":"2026-10-06T08:45:28.438Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-10-06 09:18:15","lastModifiedDate":"2026-10-06 09:18:15","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98265","Ordinal":"1","Title":"ALSA: usb-audio: Clamp implicit feedback packet count to URB cap","CVE":"CVE-2026-98265","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98265","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"ALSA: usb-audio: Clamp implicit feedback packet count to URB cap"}]}}}