{"api_version":"1","generated_at":"2026-11-07T15:53:37+00:00","cve":"CVE-2026-99271","urls":{"html":"https://cve.report/CVE-2026-99271","api":"https://cve.report/api/cve/CVE-2026-99271.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-99271","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-99271"},"summary":{"title":"ALSA: line6: Clear prev_fbuf on capture buffer release","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: line6: Clear prev_fbuf on capture buffer release\n\nA KASAN slab-use-after-free read was reported in submit_audio_out_urb()\nwhen generating an impulse test signal:\n\n  BUG: KASAN: slab-use-after-free in create_impulse_test_signal sound/usb/line6/playback.c:76 [inline]\n  BUG: KASAN: slab-use-after-free in submit_audio_out_urb+0x1848/0x1b20 sound/usb/line6/playback.c:249\n  Read of size 2 at addr ffff888008d74870 by task syz.2.3214/7785\n\n  Allocated by task 11:\n   kmem_cache_alloc_noprof+0x2f0/0x390 mm/slub.c:4144\n   line6_buffer_acquire+0x1a1/0x220 sound/usb/line6/pcm.c:158\n   line6_pcm_acquire+0xb6/0x230 sound/usb/line6/pcm.c:329\n   line6_startup_work+0x3c/0x50 sound/usb/line6/driver.c:728\n\n  Freed by task 7785:\n   kfree+0xf8/0x390 mm/slub.c:6566\n   line6_buffer_release sound/usb/line6/pcm.c:176 [inline]\n   line6_buffer_release+0xa5/0xf0 sound/usb/line6/pcm.c:170\n   __line6_pcm_release sound/usb/line6/pcm.c:305 [inline]\n   line6_pcm_release+0x5a/0x80 sound/usb/line6/pcm.c:313\n   snd_toneport_monitor_put+0x11b/0x190 sound/usb/line6/toneport.c:183\n\nline6pcm->prev_fbuf points into the capture PCM stream buffer\n(line6pcm->in.buffer), which is updated during audio_in_callback() to\nfeed rate synchronization, software monitoring, and impulse test signal\ngeneration on playback side.\n\nWhen all capture streams are closed, line6_buffer_release() frees\npstr->buffer with kfree().  However, it does not clear line6pcm->prev_fbuf.\nIf playback is subsequently started (e.g. via impulse test signal\nvolume control snd_line6_impulse_volume_put()), submit_audio_out_urb()\ndereferences the stale pointer line6pcm->prev_fbuf under in.lock,\nresulting in a slab-use-after-free read.\n\nClear prev_fbuf and prev_fsize in line6_buffer_release() when releasing\nthe capture stream buffer under in.lock, ensuring that no stale buffer\npointer can be accessed by submit_audio_out_urb().","state":"PUBLISHED","assigner":"Linux","published_at":"2026-11-07 14:17:02","updated_at":"2026-11-07 14:17:02"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/aa118c8f61d59387961d58ffae831c5259a9f222","name":"https://git.kernel.org/stable/c/aa118c8f61d59387961d58ffae831c5259a9f222","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/862d9268f40a6e10cef24eb226e738fb69ce8aa7","name":"https://git.kernel.org/stable/c/862d9268f40a6e10cef24eb226e738fb69ce8aa7","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/22c82f33ff0b68d37041adf1dea5533a5863cd31","name":"https://git.kernel.org/stable/c/22c82f33ff0b68d37041adf1dea5533a5863cd31","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-99271","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-99271","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 63e20df1e5b2ef8d871ecbdb6c038d554ed1ca74 862d9268f40a6e10cef24eb226e738fb69ce8aa7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 63e20df1e5b2ef8d871ecbdb6c038d554ed1ca74 22c82f33ff0b68d37041adf1dea5533a5863cd31 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 63e20df1e5b2ef8d871ecbdb6c038d554ed1ca74 aa118c8f61d59387961d58ffae831c5259a9f222 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.0","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 4.0 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.61 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3.2 7.3.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.4-rc1 * 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/pcm.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"862d9268f40a6e10cef24eb226e738fb69ce8aa7","status":"affected","version":"63e20df1e5b2ef8d871ecbdb6c038d554ed1ca74","versionType":"git"},{"lessThan":"22c82f33ff0b68d37041adf1dea5533a5863cd31","status":"affected","version":"63e20df1e5b2ef8d871ecbdb6c038d554ed1ca74","versionType":"git"},{"lessThan":"aa118c8f61d59387961d58ffae831c5259a9f222","status":"affected","version":"63e20df1e5b2ef8d871ecbdb6c038d554ed1ca74","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["sound/usb/line6/pcm.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"4.0"},{"lessThan":"4.0","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.61","versionType":"semver"},{"lessThanOrEqual":"7.3.*","status":"unaffected","version":"7.3.2","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.4-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.61","versionStartIncluding":"4.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3.2","versionStartIncluding":"4.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.4-rc1","versionStartIncluding":"4.0","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: line6: Clear prev_fbuf on capture buffer release\n\nA KASAN slab-use-after-free read was reported in submit_audio_out_urb()\nwhen generating an impulse test signal:\n\n  BUG: KASAN: slab-use-after-free in create_impulse_test_signal sound/usb/line6/playback.c:76 [inline]\n  BUG: KASAN: slab-use-after-free in submit_audio_out_urb+0x1848/0x1b20 sound/usb/line6/playback.c:249\n  Read of size 2 at addr ffff888008d74870 by task syz.2.3214/7785\n\n  Allocated by task 11:\n   kmem_cache_alloc_noprof+0x2f0/0x390 mm/slub.c:4144\n   line6_buffer_acquire+0x1a1/0x220 sound/usb/line6/pcm.c:158\n   line6_pcm_acquire+0xb6/0x230 sound/usb/line6/pcm.c:329\n   line6_startup_work+0x3c/0x50 sound/usb/line6/driver.c:728\n\n  Freed by task 7785:\n   kfree+0xf8/0x390 mm/slub.c:6566\n   line6_buffer_release sound/usb/line6/pcm.c:176 [inline]\n   line6_buffer_release+0xa5/0xf0 sound/usb/line6/pcm.c:170\n   __line6_pcm_release sound/usb/line6/pcm.c:305 [inline]\n   line6_pcm_release+0x5a/0x80 sound/usb/line6/pcm.c:313\n   snd_toneport_monitor_put+0x11b/0x190 sound/usb/line6/toneport.c:183\n\nline6pcm->prev_fbuf points into the capture PCM stream buffer\n(line6pcm->in.buffer), which is updated during audio_in_callback() to\nfeed rate synchronization, software monitoring, and impulse test signal\ngeneration on playback side.\n\nWhen all capture streams are closed, line6_buffer_release() frees\npstr->buffer with kfree().  However, it does not clear line6pcm->prev_fbuf.\nIf playback is subsequently started (e.g. via impulse test signal\nvolume control snd_line6_impulse_volume_put()), submit_audio_out_urb()\ndereferences the stale pointer line6pcm->prev_fbuf under in.lock,\nresulting in a slab-use-after-free read.\n\nClear prev_fbuf and prev_fsize in line6_buffer_release() when releasing\nthe capture stream buffer under in.lock, ensuring that no stale buffer\npointer can be accessed by submit_audio_out_urb()."}],"providerMetadata":{"dateUpdated":"2026-11-07T14:08:45.047Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/862d9268f40a6e10cef24eb226e738fb69ce8aa7"},{"url":"https://git.kernel.org/stable/c/22c82f33ff0b68d37041adf1dea5533a5863cd31"},{"url":"https://git.kernel.org/stable/c/aa118c8f61d59387961d58ffae831c5259a9f222"}],"title":"ALSA: line6: Clear prev_fbuf on capture buffer release","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-99271","datePublished":"2026-11-07T14:08:45.047Z","dateReserved":"2026-09-25T10:25:14.404Z","dateUpdated":"2026-11-07T14:08:45.047Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-11-07 14:17:02","lastModifiedDate":"2026-11-07 14:17:02","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"99271","Ordinal":"1","Title":"ALSA: line6: Clear prev_fbuf on capture buffer release","CVE":"CVE-2026-99271","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"99271","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: line6: Clear prev_fbuf on capture buffer release\n\nA KASAN slab-use-after-free read was reported in submit_audio_out_urb()\nwhen generating an impulse test signal:\n\n  BUG: KASAN: slab-use-after-free in create_impulse_test_signal sound/usb/line6/playback.c:76 [inline]\n  BUG: KASAN: slab-use-after-free in submit_audio_out_urb+0x1848/0x1b20 sound/usb/line6/playback.c:249\n  Read of size 2 at addr ffff888008d74870 by task syz.2.3214/7785\n\n  Allocated by task 11:\n   kmem_cache_alloc_noprof+0x2f0/0x390 mm/slub.c:4144\n   line6_buffer_acquire+0x1a1/0x220 sound/usb/line6/pcm.c:158\n   line6_pcm_acquire+0xb6/0x230 sound/usb/line6/pcm.c:329\n   line6_startup_work+0x3c/0x50 sound/usb/line6/driver.c:728\n\n  Freed by task 7785:\n   kfree+0xf8/0x390 mm/slub.c:6566\n   line6_buffer_release sound/usb/line6/pcm.c:176 [inline]\n   line6_buffer_release+0xa5/0xf0 sound/usb/line6/pcm.c:170\n   __line6_pcm_release sound/usb/line6/pcm.c:305 [inline]\n   line6_pcm_release+0x5a/0x80 sound/usb/line6/pcm.c:313\n   snd_toneport_monitor_put+0x11b/0x190 sound/usb/line6/toneport.c:183\n\nline6pcm->prev_fbuf points into the capture PCM stream buffer\n(line6pcm->in.buffer), which is updated during audio_in_callback() to\nfeed rate synchronization, software monitoring, and impulse test signal\ngeneration on playback side.\n\nWhen all capture streams are closed, line6_buffer_release() frees\npstr->buffer with kfree().  However, it does not clear line6pcm->prev_fbuf.\nIf playback is subsequently started (e.g. via impulse test signal\nvolume control snd_line6_impulse_volume_put()), submit_audio_out_urb()\ndereferences the stale pointer line6pcm->prev_fbuf under in.lock,\nresulting in a slab-use-after-free read.\n\nClear prev_fbuf and prev_fsize in line6_buffer_release() when releasing\nthe capture stream buffer under in.lock, ensuring that no stale buffer\npointer can be accessed by submit_audio_out_urb().","Type":"Description","Title":"ALSA: line6: Clear prev_fbuf on capture buffer release"}]}}}