{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-81007",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-08-26T14:34:25.812Z",
        "datePublished": "2026-09-11T19:42:58.751Z",
        "dateUpdated": "2026-10-19T08:46:32.534Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-10-19T08:46:32.534Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipmi: ipmb: validate write message length\n\nipmb_write() read message fields before validating the length byte.\n\nA zero or short write can read uninitialized stack bytes.\n\nA length smaller than the SMBus header underflows the block write length.\n\nRequire a non-empty buffer and the minimum IPMB request length.\n\nAlso require the length byte plus payload before parsing the message."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
                        "baseScore": 7.1,
                        "baseSeverity": "HIGH"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:L - ipmb_write() is the miscdevice write handler for /dev/ipmb-N and is reached only via a local write(2) on that character device. The I2C slave callback queues inbound IPMB requests for read() and does not enter this path.\nAC:L - A single write of count 0, or a 1-byte write with length field 0, bypasses the old count<msg[0] check and underflows the I2C/SMBus length. The attacker fully controls the buffer; no race or uninfluenced memory layout is required.\nPR:L - Neither ipmb_write() nor misc_open() performs a capability check; access is only DAC on /dev/ipmb-N. BMC and satellite-MC deployments (OpenBMC ipmbbridge, OpenIPMI) commonly grant this node to a non-root management or service account rather than requiring init-namespace root.\nUI:N - The attacker triggers the bug entirely with their own write(2) to an already-present /dev/ipmb-N node. No other user must open a file, mount a filesystem, or otherwise interact.\nS:U - The out-of-bounds stack read and resulting kernel oops remain inside the same host kernel security authority. IPMB/I2C is an in-chassis management bus, not a VM, IOMMU, or sandbox boundary crossing.\nC:H - On i2c-protocol devices (usual OpenBMC/Aspeed DT), a zero length byte promotes to i2c_msg.len 65535, so i2c_transfer/DMA helpers read tens of kilobytes past the 240-byte stack buffer, disclosing kernel stack contents onto the IPMB bus.\nI:N - The defect is an out-of-bounds read of a stack buffer used as an I2C write payload. It does not write kernel memory, corrupt heap objects, or yield a control-flow or arbitrary-write primitive.\nA:H - The 65535-byte stack over-read walks off the kernel stack. Aspeed I2C (typical OpenBMC IPMB adapter) has no max_write_len quirk, so the transfer or memcpy hits the VMAP_STACK guard page and oopses the kernel."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/char/ipmi/ipmb_dev_int.c"
                    ],
                    "versions": [
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                            "version": "51bd6f291583684f495ea498984dfc22049d7fd2",
                            "lessThan": "8990c7f6bfc1e7689b7012a7d4d0efb9f07a9c89",
                            "status": "affected",
                            "versionType": "git"
                        },
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                            "lessThan": "94f8d20153e348c79bc14dc25f873470518892da",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "51bd6f291583684f495ea498984dfc22049d7fd2",
                            "lessThan": "e527cd4e80066e1ed070fdc7c705bde340cdcc62",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "51bd6f291583684f495ea498984dfc22049d7fd2",
                            "lessThan": "7d66d54b974cff0a959e188af844d2d110422767",
                            "status": "affected",
                            "versionType": "git"
                        },
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                            "lessThan": "60939bcda6f3f104ef456fdbf3cc5733c0720fb1",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "51bd6f291583684f495ea498984dfc22049d7fd2",
                            "lessThan": "5719431ca2b5fa26560bb38f6202f8b97fa3bbb0",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "51bd6f291583684f495ea498984dfc22049d7fd2",
                            "lessThan": "a84c6e3d188f2c6e674910929eb790634299d6d5",
                            "status": "affected",
                            "versionType": "git"
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                            "version": "51bd6f291583684f495ea498984dfc22049d7fd2",
                            "lessThan": "53637506884dbd5c91a89b1a3547d99d80f8ed2c",
                            "status": "affected",
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                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/char/ipmi/ipmb_dev_int.c"
                    ],
                    "versions": [
                        {
                            "version": "5.3",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.3",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.10.270",
                            "lessThanOrEqual": "5.10.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.15.221",
                            "lessThanOrEqual": "5.15.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1.188",
                            "lessThanOrEqual": "6.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.157",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.109",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.50",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.4",
                            "lessThanOrEqual": "7.2.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.3",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
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                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                                    "versionEndExcluding": "5.10.270"
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            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/8990c7f6bfc1e7689b7012a7d4d0efb9f07a9c89"
                },
                {
                    "url": "https://git.kernel.org/stable/c/94f8d20153e348c79bc14dc25f873470518892da"
                },
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                    "url": "https://git.kernel.org/stable/c/e527cd4e80066e1ed070fdc7c705bde340cdcc62"
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                    "url": "https://git.kernel.org/stable/c/7d66d54b974cff0a959e188af844d2d110422767"
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                    "url": "https://git.kernel.org/stable/c/60939bcda6f3f104ef456fdbf3cc5733c0720fb1"
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                    "url": "https://git.kernel.org/stable/c/5719431ca2b5fa26560bb38f6202f8b97fa3bbb0"
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                    "url": "https://git.kernel.org/stable/c/a84c6e3d188f2c6e674910929eb790634299d6d5"
                },
                {
                    "url": "https://git.kernel.org/stable/c/53637506884dbd5c91a89b1a3547d99d80f8ed2c"
                }
            ],
            "title": "ipmi: ipmb: validate write message length",
            "x_generator": {
                "engine": "bippy-1.2.0"
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    }
}