{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-64479",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-07-19T15:36:31.791Z",
        "datePublished": "2026-07-25T08:51:41.006Z",
        "dateUpdated": "2026-08-17T04:56:25.868Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-17T04:56:25.868Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: seq: Fix uninitialised heap leak in snd_seq_event_dup()\n\nsnd_seq_event_dup() copies an incoming event into a pool cell and, in\nthe UMP-enabled build, clears the trailing cell->ump.raw.extra word that\nthe memcpy() did not cover.  The guard deciding whether to clear it\ncompares the copied size against sizeof(cell->event):\n\n\tmemcpy(&cell->ump, event, size);\n\tif (size < sizeof(cell->event))\n\t\tcell->ump.raw.extra = 0;\n\nFor a legacy (non-UMP) event, size == sizeof(struct snd_seq_event) ==\nsizeof(cell->event), so the condition is false and the extra word keeps\nstale data.  The cell pool is allocated with kvmalloc() (not zeroed) and\ncells are reused via a free list, so that word holds uninitialised heap\nor leftover event data.\n\nWhen such a cell is delivered to a UMP client (client->midi_version > 0)\nthat set SNDRV_SEQ_FILTER_NO_CONVERT -- so the legacy event reaches it\nunconverted -- snd_seq_read() reads it out as the larger struct\nsnd_seq_ump_event and copies the stale word to user space, a 4-byte\nkernel heap infoleak to an unprivileged /dev/snd/seq client.\n\nCompare against sizeof(cell->ump) instead, so the trailing word is zeroed\nfor every event shorter than the UMP cell."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "sound/core/seq/seq_memory.c"
                    ],
                    "versions": [
                        {
                            "version": "6389f2c135311c4ce7c08c3b29145c8f95aacf1f",
                            "lessThan": "d7649aa11089a93ea2285c210397aa67e5800766",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "d7e2ce72833bb23a82b4201fbed7214cc04a4a8c",
                            "lessThan": "a224c84e5d3d35708c082c84ad12d81d90762195",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "46397622a3fa8372b8fda0f04b33d16923b03b1b",
                            "lessThan": "ea672a9f6cc38f06fe69dd2c257ef8a3d4db179a",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "46397622a3fa8372b8fda0f04b33d16923b03b1b",
                            "lessThan": "fb1aa5082847b98f44f9c6272aee9d0dca9244f0",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "46397622a3fa8372b8fda0f04b33d16923b03b1b",
                            "lessThan": "651ba82fe2a144bc7356d940bfd235c3810b0549",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "46397622a3fa8372b8fda0f04b33d16923b03b1b",
                            "lessThan": "6ded42615fa1f4949925afd0a8a9e1ab3bf96202",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "46397622a3fa8372b8fda0f04b33d16923b03b1b",
                            "lessThan": "435990e25bf1f4af3e6df12a6fbfd1f7ba4a97d4",
                            "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/core/seq/seq_memory.c"
                    ],
                    "versions": [
                        {
                            "version": "6.5",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.5",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.145",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.96",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.39",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1.4",
                            "lessThanOrEqual": "7.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2",
                            "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": "6.5",
                                    "versionEndExcluding": "6.6.145"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.5",
                                    "versionEndExcluding": "6.12.96"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.5",
                                    "versionEndExcluding": "6.18.39"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.5",
                                    "versionEndExcluding": "7.1.4"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.5",
                                    "versionEndExcluding": "7.2"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/d7649aa11089a93ea2285c210397aa67e5800766"
                },
                {
                    "url": "https://git.kernel.org/stable/c/a224c84e5d3d35708c082c84ad12d81d90762195"
                },
                {
                    "url": "https://git.kernel.org/stable/c/ea672a9f6cc38f06fe69dd2c257ef8a3d4db179a"
                },
                {
                    "url": "https://git.kernel.org/stable/c/fb1aa5082847b98f44f9c6272aee9d0dca9244f0"
                },
                {
                    "url": "https://git.kernel.org/stable/c/651ba82fe2a144bc7356d940bfd235c3810b0549"
                },
                {
                    "url": "https://git.kernel.org/stable/c/6ded42615fa1f4949925afd0a8a9e1ab3bf96202"
                },
                {
                    "url": "https://git.kernel.org/stable/c/435990e25bf1f4af3e6df12a6fbfd1f7ba4a97d4"
                }
            ],
            "title": "ALSA: seq: Fix uninitialised heap leak in snd_seq_event_dup()",
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    }
}