{"api_version":"1","generated_at":"2026-10-21T11:52:31+00:00","cve":"CVE-2026-98836","urls":{"html":"https://cve.report/CVE-2026-98836","api":"https://cve.report/api/cve/CVE-2026-98836.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98836","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98836"},"summary":{"title":"ALSA: line6: reject oversized playback packets","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: line6: reject oversized playback packets\n\nEach playback URB is handed a slice of out.buffer that is exactly\nLINE6_ISO_PACKETS * max_packet_size_out bytes, sized from the OUT\nendpoint, but the number of bytes written into that slice is never\ncompared against it.\n\nsubmit_audio_out_urb() takes the frame count from prev_fsize, which\naudio_in_callback() derived from the *IN* endpoint's received packet\nlength, and rescales it with the playback frame size; when prev_fsize is\nstill zero it synthesizes a length from the sample rate instead.  On a\ndevice declaring a large IN wMaxPacketSize and a small OUT\nwMaxPacketSize, the resulting memcpy(), or the memset() when the\nplayback stream is idle, runs past its slice and, as the reproducer\nbelow shows, beyond the allocation.\n\nusb_submit_urb() is not a backstop.  max_packet_size_out comes from\nusb_maxpacket(), which returns only the low 11 bits of wMaxPacketSize,\nwhile USB core validates a high-speed isochronous length against that\nbase scaled by usb_endpoint_maxp_mult().  A length of up to three times\nthe allocated slice is therefore accepted, and even a rejected URB is\nonly rejected after the write.\n\nReject a packet that does not fit the slice the driver allocated for it.\nClamping it instead would silently shorten the capture-derived rate\nfeedback and desynchronize the two streams.\n\n  BUG: KASAN: slab-out-of-bounds in submit_audio_out_urb (sound/usb/line6/playback.c:229)\n  Write of size 1024 at addr ffff888100bbd400 by task kworker/1:2/5002\n  Workqueue: events line6_startup_work\n  Call Trace:\n   __asan_memcpy (mm/kasan/shadow.c:106)\n   submit_audio_out_urb (sound/usb/line6/playback.c:229)\n   line6_submit_audio_out_all_urbs (sound/usb/line6/playback.c:291)\n   line6_stream_start (sound/usb/line6/pcm.c:194)\n   line6_pcm_acquire (sound/usb/line6/pcm.c:337)\n   line6_startup_work (sound/usb/line6/driver.c:728)\n   process_one_work (kernel/workqueue.c:3396)\n   worker_thread (kernel/workqueue.c:3479 kernel/workqueue.c:3560)\n   kthread (kernel/kthread.c:436)\n   ret_from_fork (arch/x86/kernel/process.c:158)\n   ret_from_fork_asm (arch/x86/entry/entry_64.S:245)\n\n  The buggy address belongs to the object at ffff888100bbd400\n   which belongs to the cache kmalloc-256 of size 256\n  The buggy address is located 0 bytes inside of\n   allocated 256-byte region [ffff888100bbd400, ffff888100bbd500)","state":"PUBLISHED","assigner":"Linux","published_at":"2026-10-18 16:17:37","updated_at":"2026-10-19 10:19:47"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/61b0a5a114fa4552892da5c0ff2f42e63bf08c6b","name":"https://git.kernel.org/stable/c/61b0a5a114fa4552892da5c0ff2f42e63bf08c6b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/a84371be89c39ccc46c7af8b9eb15c448df9265f","name":"https://git.kernel.org/stable/c/a84371be89c39ccc46c7af8b9eb15c448df9265f","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/3f75da1e4ee699f6650d23d6897cf443b01856c7","name":"https://git.kernel.org/stable/c/3f75da1e4ee699f6650d23d6897cf443b01856c7","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b78748424f29f07d310484b2b36afdececa74389","name":"https://git.kernel.org/stable/c/b78748424f29f07d310484b2b36afdececa74389","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98836","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98836","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7a0f55aeeb8f1fa32a119d34ddfefc6100936692 a84371be89c39ccc46c7af8b9eb15c448df9265f git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7a0f55aeeb8f1fa32a119d34ddfefc6100936692 3f75da1e4ee699f6650d23d6897cf443b01856c7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7a0f55aeeb8f1fa32a119d34ddfefc6100936692 b78748424f29f07d310484b2b36afdececa74389 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7a0f55aeeb8f1fa32a119d34ddfefc6100936692 61b0a5a114fa4552892da5c0ff2f42e63bf08c6b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.9","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 4.9 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.113 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.56 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.10 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["sound/usb/line6/playback.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"a84371be89c39ccc46c7af8b9eb15c448df9265f","status":"affected","version":"7a0f55aeeb8f1fa32a119d34ddfefc6100936692","versionType":"git"},{"lessThan":"3f75da1e4ee699f6650d23d6897cf443b01856c7","status":"affected","version":"7a0f55aeeb8f1fa32a119d34ddfefc6100936692","versionType":"git"},{"lessThan":"b78748424f29f07d310484b2b36afdececa74389","status":"affected","version":"7a0f55aeeb8f1fa32a119d34ddfefc6100936692","versionType":"git"},{"lessThan":"61b0a5a114fa4552892da5c0ff2f42e63bf08c6b","status":"affected","version":"7a0f55aeeb8f1fa32a119d34ddfefc6100936692","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["sound/usb/line6/playback.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"4.9"},{"lessThan":"4.9","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.113","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.56","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.10","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.113","versionStartIncluding":"4.9","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.56","versionStartIncluding":"4.9","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.10","versionStartIncluding":"4.9","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3","versionStartIncluding":"4.9","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: line6: reject oversized playback packets\n\nEach playback URB is handed a slice of out.buffer that is exactly\nLINE6_ISO_PACKETS * max_packet_size_out bytes, sized from the OUT\nendpoint, but the number of bytes written into that slice is never\ncompared against it.\n\nsubmit_audio_out_urb() takes the frame count from prev_fsize, which\naudio_in_callback() derived from the *IN* endpoint's received packet\nlength, and rescales it with the playback frame size; when prev_fsize is\nstill zero it synthesizes a length from the sample rate instead.  On a\ndevice declaring a large IN wMaxPacketSize and a small OUT\nwMaxPacketSize, the resulting memcpy(), or the memset() when the\nplayback stream is idle, runs past its slice and, as the reproducer\nbelow shows, beyond the allocation.\n\nusb_submit_urb() is not a backstop.  max_packet_size_out comes from\nusb_maxpacket(), which returns only the low 11 bits of wMaxPacketSize,\nwhile USB core validates a high-speed isochronous length against that\nbase scaled by usb_endpoint_maxp_mult().  A length of up to three times\nthe allocated slice is therefore accepted, and even a rejected URB is\nonly rejected after the write.\n\nReject a packet that does not fit the slice the driver allocated for it.\nClamping it instead would silently shorten the capture-derived rate\nfeedback and desynchronize the two streams.\n\n  BUG: KASAN: slab-out-of-bounds in submit_audio_out_urb (sound/usb/line6/playback.c:229)\n  Write of size 1024 at addr ffff888100bbd400 by task kworker/1:2/5002\n  Workqueue: events line6_startup_work\n  Call Trace:\n   __asan_memcpy (mm/kasan/shadow.c:106)\n   submit_audio_out_urb (sound/usb/line6/playback.c:229)\n   line6_submit_audio_out_all_urbs (sound/usb/line6/playback.c:291)\n   line6_stream_start (sound/usb/line6/pcm.c:194)\n   line6_pcm_acquire (sound/usb/line6/pcm.c:337)\n   line6_startup_work (sound/usb/line6/driver.c:728)\n   process_one_work (kernel/workqueue.c:3396)\n   worker_thread (kernel/workqueue.c:3479 kernel/workqueue.c:3560)\n   kthread (kernel/kthread.c:436)\n   ret_from_fork (arch/x86/kernel/process.c:158)\n   ret_from_fork_asm (arch/x86/entry/entry_64.S:245)\n\n  The buggy address belongs to the object at ffff888100bbd400\n   which belongs to the cache kmalloc-256 of size 256\n  The buggy address is located 0 bytes inside of\n   allocated 256-byte region [ffff888100bbd400, ffff888100bbd500)"}],"providerMetadata":{"dateUpdated":"2026-10-19T09:26:28.639Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/a84371be89c39ccc46c7af8b9eb15c448df9265f"},{"url":"https://git.kernel.org/stable/c/3f75da1e4ee699f6650d23d6897cf443b01856c7"},{"url":"https://git.kernel.org/stable/c/b78748424f29f07d310484b2b36afdececa74389"},{"url":"https://git.kernel.org/stable/c/61b0a5a114fa4552892da5c0ff2f42e63bf08c6b"}],"title":"ALSA: line6: reject oversized playback packets","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98836","datePublished":"2026-10-18T15:49:51.823Z","dateReserved":"2026-09-25T10:25:14.372Z","dateUpdated":"2026-10-19T09:26:28.639Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-10-18 16:17:37","lastModifiedDate":"2026-10-19 10:19:47","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98836","Ordinal":"1","Title":"ALSA: line6: reject oversized playback packets","CVE":"CVE-2026-98836","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98836","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: line6: reject oversized playback packets\n\nEach playback URB is handed a slice of out.buffer that is exactly\nLINE6_ISO_PACKETS * max_packet_size_out bytes, sized from the OUT\nendpoint, but the number of bytes written into that slice is never\ncompared against it.\n\nsubmit_audio_out_urb() takes the frame count from prev_fsize, which\naudio_in_callback() derived from the *IN* endpoint's received packet\nlength, and rescales it with the playback frame size; when prev_fsize is\nstill zero it synthesizes a length from the sample rate instead.  On a\ndevice declaring a large IN wMaxPacketSize and a small OUT\nwMaxPacketSize, the resulting memcpy(), or the memset() when the\nplayback stream is idle, runs past its slice and, as the reproducer\nbelow shows, beyond the allocation.\n\nusb_submit_urb() is not a backstop.  max_packet_size_out comes from\nusb_maxpacket(), which returns only the low 11 bits of wMaxPacketSize,\nwhile USB core validates a high-speed isochronous length against that\nbase scaled by usb_endpoint_maxp_mult().  A length of up to three times\nthe allocated slice is therefore accepted, and even a rejected URB is\nonly rejected after the write.\n\nReject a packet that does not fit the slice the driver allocated for it.\nClamping it instead would silently shorten the capture-derived rate\nfeedback and desynchronize the two streams.\n\n  BUG: KASAN: slab-out-of-bounds in submit_audio_out_urb (sound/usb/line6/playback.c:229)\n  Write of size 1024 at addr ffff888100bbd400 by task kworker/1:2/5002\n  Workqueue: events line6_startup_work\n  Call Trace:\n   __asan_memcpy (mm/kasan/shadow.c:106)\n   submit_audio_out_urb (sound/usb/line6/playback.c:229)\n   line6_submit_audio_out_all_urbs (sound/usb/line6/playback.c:291)\n   line6_stream_start (sound/usb/line6/pcm.c:194)\n   line6_pcm_acquire (sound/usb/line6/pcm.c:337)\n   line6_startup_work (sound/usb/line6/driver.c:728)\n   process_one_work (kernel/workqueue.c:3396)\n   worker_thread (kernel/workqueue.c:3479 kernel/workqueue.c:3560)\n   kthread (kernel/kthread.c:436)\n   ret_from_fork (arch/x86/kernel/process.c:158)\n   ret_from_fork_asm (arch/x86/entry/entry_64.S:245)\n\n  The buggy address belongs to the object at ffff888100bbd400\n   which belongs to the cache kmalloc-256 of size 256\n  The buggy address is located 0 bytes inside of\n   allocated 256-byte region [ffff888100bbd400, ffff888100bbd500)","Type":"Description","Title":"ALSA: line6: reject oversized playback packets"}]}}}