{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-44954", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-08-21T05:34:56.666Z", "datePublished": "2024-09-04T18:35:53.730Z", "dateUpdated": "2026-08-05T11:37:18.083Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:37:18.083Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: line6: Fix racy access to midibuf\n\nThere can be concurrent accesses to line6 midibuf from both the URB\ncompletion callback and the rawmidi API access. This could be a cause\nof KMSAN warning triggered by syzkaller below (so put as reported-by\nhere).\n\nThis patch protects the midibuf call of the former code path with a\nspinlock for avoiding the possible races." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The unsynchronized accesses are in `line6_data_received()` (URB completion for the control/MIDI-in endpoint) racing the rawmidi API path, and the driver is only bound when a Line 6 device is already attached — so a local unprivileged user on such a host drives both halves via `/dev/snd/midiC*D*` (and the hwdep node), writing MIDI/sysex to solicit device replies that generate URB completions while concurrently hammering rawmidi read/trigger. No physical access by the attacker is needed in that deployment (audio workstation, live-performance rig).\nAC:L - The attacker controls both sides of the race — one thread issues rawmidi/hwdep writes that make the device respond on the interrupt-in endpoint, another thread concurrently exercises the rawmidi API — and the window can be retried indefinitely at MIDI packet rate. Per the guidance, a race whose both sides the attacker creates is Low.\nPR:L - Only ordinary access to the ALSA rawmidi/hwdep character devices is required, which the console/desktop user gets by default through udev ACLs or `audio` group membership. No CAP_SYS_ADMIN or root is needed.\nUI:N - The attacker performs every step itself — opening the rawmidi node, soliciting device traffic, and racing the accesses. Presence of the Line 6 device is a property of the affected system (the driver does not load otherwise), not a victim action during the attack.\nS:U - The corrupted ring-buffer state, the heap over-read, and the disclosed data all live in the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - syzbot confirmed \"KMSAN: uninit-value in line6_midibuf_read\" at `midibuf.c:185` — racy `pos_read`/`pos_write`/`full` make the reader consume bytes never written, so stale contents of the `kmalloc()`ed 1024-byte `midi_buffer.buf` slab object are memcpy'd into `line6->buffer_message` and delivered to userspace through `snd_rawmidi_receive()`. A stale `length1 = size - pos_write`/`pos_read` pair also lets the copy index past the end of that allocation, and the leak is repeatable, allowing kernel heap contents (pointers, recycled data) to be harvested.\nI:H - `line6_midibuf_write()` computes `length1 = this->size - this->pos_write` and then does `memcpy(this->buf + this->pos_write, data, length1)` re-reading `pos_write`; with no lock, a concurrent index update makes that copy run past the end of the kmalloc-1024 object with device-supplied MIDI bytes, giving an attacker-influenced heap out-of-bounds write, and corrupted indices also feed bogus data into the rawmidi stream.\nA:H - Out-of-bounds reads and writes on the kmalloc-1024 slab object corrupt adjacent allocations and trip sanitizer/hardening checks, producing oops or panic. The bug is a memory-safety error, which per the guidance is High availability impact." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "sound/usb/line6/driver.c" ], "versions": [ { "version": "705ececd1c60d0f5d6ef2a719008847883516970", "lessThan": "643293b68fbb6c03f5e907736498da17d43f0d81", "status": "affected", "versionType": "git" }, { "version": "705ececd1c60d0f5d6ef2a719008847883516970", "lessThan": "40f3d5cb0e0cbf7fa697913a27d5d361373bdcf5", "status": "affected", "versionType": "git" }, { "version": "705ececd1c60d0f5d6ef2a719008847883516970", "lessThan": "e7e7d2b180d8f297cea6db43ea72402fd33e1a29", "status": "affected", "versionType": "git" }, { "version": "705ececd1c60d0f5d6ef2a719008847883516970", "lessThan": "a54da4b787dcac60b598da69c9c0072812b8282d", "status": "affected", "versionType": "git" }, { "version": "705ececd1c60d0f5d6ef2a719008847883516970", "lessThan": "c80f454a805443c274394b1db0d1ebf477abd94e", "status": "affected", "versionType": "git" }, { "version": "705ececd1c60d0f5d6ef2a719008847883516970", "lessThan": "535df7f896a568a8a1564114eaea49d002cb1747", "status": "affected", "versionType": "git" }, { "version": "705ececd1c60d0f5d6ef2a719008847883516970", "lessThan": "51d87f11dd199bbc6a85982b088ff27bde53b48a", "status": "affected", "versionType": "git" }, { "version": "705ececd1c60d0f5d6ef2a719008847883516970", "lessThan": "15b7a03205b31bc5623378c190d22b7ff60026f1", "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/line6/driver.c" ], "versions": [ { "version": "2.6.30", "status": "affected" }, { "version": "0", "lessThan": "2.6.30", "status": "unaffected", "versionType": "semver" }, { "version": "4.19.320", "lessThanOrEqual": "4.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.282", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.224", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.165", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.105", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.46", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.10.5", "lessThanOrEqual": "6.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.11", "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": "2.6.30", "versionEndExcluding": "4.19.320" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "5.4.282" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "5.10.224" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "5.15.165" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "6.1.105" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "6.6.46" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "6.10.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "6.11" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/643293b68fbb6c03f5e907736498da17d43f0d81" }, { "url": "https://git.kernel.org/stable/c/40f3d5cb0e0cbf7fa697913a27d5d361373bdcf5" }, { "url": "https://git.kernel.org/stable/c/e7e7d2b180d8f297cea6db43ea72402fd33e1a29" }, { "url": "https://git.kernel.org/stable/c/a54da4b787dcac60b598da69c9c0072812b8282d" }, { "url": "https://git.kernel.org/stable/c/c80f454a805443c274394b1db0d1ebf477abd94e" }, { "url": "https://git.kernel.org/stable/c/535df7f896a568a8a1564114eaea49d002cb1747" }, { "url": "https://git.kernel.org/stable/c/51d87f11dd199bbc6a85982b088ff27bde53b48a" }, { "url": "https://git.kernel.org/stable/c/15b7a03205b31bc5623378c190d22b7ff60026f1" } ], "title": "ALSA: line6: Fix racy access to midibuf", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2024-44954", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2024-09-10T17:40:10.329711Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-09-12T17:33:34.296Z" } }, { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html" }, { "url": "https://lists.debian.org/debian-lts-announce/2024/10/msg00003.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T22:14:04.124Z" } } ] } }