{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-99203",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-09-25T10:25:14.400Z",
        "datePublished": "2026-10-28T10:35:57.589Z",
        "dateUpdated": "2026-10-30T12:42:53.265Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-10-30T12:42:53.265Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npipe: preserve existing fasync readers on writer setup failure\n\nF_SETFL and FIOASYNC decide whether to invoke ->fasync() before\npipe_fasync() takes pipe->mutex. Two enables of one O_RDWR FIFO can\ntherefore both enter the callback.\n\nfasync_helper() allocates before checking for an existing entry. If the\nfirst enable installs both entries, a second enable can update the\nreader entry and then fail the allocation for the writer entry. The\nerror path removes the pre-existing reader entry, clearing FASYNC while\nthe writer entry remains registered. __fput() then skips ->fasync(), so a\nlater pipe notification can dereference the freed file or its f_owner.\nAn unprivileged memory-pressure reproducer triggers a KASAN\nslab-use-after-free in send_sigio() through this path.\n\nKeep the reader helper's result and undo the registration only if this\ncall added it. The pipe mutex serializes changes to both lists, so a\nfailed new registration still removes its reader, while a failed\nduplicate preserves the existing registrations and FASYNC. Successful\nduplicate enables continue to update fa_fd as before."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/pipe.c"
                    ],
                    "versions": [
                        {
                            "version": "76398425bb06b07cc3a3b1ce169c67dc9d6874ed",
                            "lessThan": "6041bcd185d4df051490fe166e64feae6c3b8291",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "76398425bb06b07cc3a3b1ce169c67dc9d6874ed",
                            "lessThan": "7cdbfa22a7e270b155ddb958b1583a999c0c8abb",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "76398425bb06b07cc3a3b1ce169c67dc9d6874ed",
                            "lessThan": "22c7f57b0c0b0b8e19cfb41a1bd85f55715ad386",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "76398425bb06b07cc3a3b1ce169c67dc9d6874ed",
                            "lessThan": "94be790dd6fbe0912f35bb711bea8ef3687eaca9",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "76398425bb06b07cc3a3b1ce169c67dc9d6874ed",
                            "lessThan": "9b0aa2a1d8df51f3dcb363c3a2d9531098e88dc6",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "76398425bb06b07cc3a3b1ce169c67dc9d6874ed",
                            "lessThan": "4c42ce499ce4b1c787e61082e3b13df4f30c4eaa",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "76398425bb06b07cc3a3b1ce169c67dc9d6874ed",
                            "lessThan": "2259809e5b7043c4ba20af7b14ba3e471cf55521",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "76398425bb06b07cc3a3b1ce169c67dc9d6874ed",
                            "lessThan": "40bb03d3ea6f6a915218508819ecc4d7a7fa260d",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/pipe.c"
                    ],
                    "versions": [
                        {
                            "version": "2.6.30",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "2.6.30",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.10.273",
                            "lessThanOrEqual": "5.10.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.15.224",
                            "lessThanOrEqual": "5.15.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1.191",
                            "lessThanOrEqual": "6.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.161",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.115",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.59",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.13",
                            "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": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.30",
                                    "versionEndExcluding": "5.10.273"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.30",
                                    "versionEndExcluding": "5.15.224"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.30",
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                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.30",
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                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                                },
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                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.30",
                                    "versionEndExcluding": "7.3"
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            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/6041bcd185d4df051490fe166e64feae6c3b8291"
                },
                {
                    "url": "https://git.kernel.org/stable/c/7cdbfa22a7e270b155ddb958b1583a999c0c8abb"
                },
                {
                    "url": "https://git.kernel.org/stable/c/22c7f57b0c0b0b8e19cfb41a1bd85f55715ad386"
                },
                {
                    "url": "https://git.kernel.org/stable/c/94be790dd6fbe0912f35bb711bea8ef3687eaca9"
                },
                {
                    "url": "https://git.kernel.org/stable/c/9b0aa2a1d8df51f3dcb363c3a2d9531098e88dc6"
                },
                {
                    "url": "https://git.kernel.org/stable/c/4c42ce499ce4b1c787e61082e3b13df4f30c4eaa"
                },
                {
                    "url": "https://git.kernel.org/stable/c/2259809e5b7043c4ba20af7b14ba3e471cf55521"
                },
                {
                    "url": "https://git.kernel.org/stable/c/40bb03d3ea6f6a915218508819ecc4d7a7fa260d"
                }
            ],
            "title": "pipe: preserve existing fasync readers on writer setup failure",
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}