{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-80920",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-08-26T14:34:25.801Z",
        "datePublished": "2026-09-09T16:13:17.023Z",
        "dateUpdated": "2026-10-21T12:47:14.401Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-10-21T12:47:14.401Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring: defer eventfd signaling when queued from a wakeup handler\n\nio_req_local_work_add() signals the CQ ring eventfd inline when it is the\none to push the first entry onto ->work_list. For DEFER_TASKRUN rings that\nadd is frequently done from a waitqueue wakeup handler, where an\narbitrary waitqueue lock is held.\n\neventfd_signal_mask() only refuses to recurse when current->in_eventfd\nis set, but that bit is set by eventfd_signal_mask() itself. If the wake\nchain starts somewhere else, signal goes out inline and can feed back\ninto epoll.\n\nAdd IOU_F_TWQ_IN_WAKE, set it on the task_work add done from the three\nwaitqueue callbacks, and use it to force io_eventfd_signal() down the\nexisting call_rcu_hurry() deferral instead of signaling inline."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "include/linux/io_uring_types.h",
                        "io_uring/eventfd.c",
                        "io_uring/eventfd.h",
                        "io_uring/futex.c",
                        "io_uring/io_uring.c",
                        "io_uring/poll.c",
                        "io_uring/tw.c",
                        "io_uring/waitid.c"
                    ],
                    "versions": [
                        {
                            "version": "21a091b970cdbcf3e8ff829234b51be6f9192766",
                            "lessThan": "d0c240f25e654442a72af5ca021a02165ccce638",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "21a091b970cdbcf3e8ff829234b51be6f9192766",
                            "lessThan": "9d984451baf768ecd9e1fdad4637b729fcb2c9d5",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "21a091b970cdbcf3e8ff829234b51be6f9192766",
                            "lessThan": "e22f4494cc9487d326e5e3067f33dea7c1e442b2",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "21a091b970cdbcf3e8ff829234b51be6f9192766",
                            "lessThan": "b6bb334b0e9348887e3e55e1f494b0c3b8fbf59f",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "21a091b970cdbcf3e8ff829234b51be6f9192766",
                            "lessThan": "40b6ccf68731809ceb85c6e9f0f8f2ed61c7aa5a",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "21a091b970cdbcf3e8ff829234b51be6f9192766",
                            "lessThan": "cd305ee3633a45fcf5f3a5d83f99f3cb77d87b6e",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "include/linux/io_uring_types.h",
                        "io_uring/eventfd.c",
                        "io_uring/eventfd.h",
                        "io_uring/futex.c",
                        "io_uring/io_uring.c",
                        "io_uring/poll.c",
                        "io_uring/tw.c",
                        "io_uring/waitid.c"
                    ],
                    "versions": [
                        {
                            "version": "6.1",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.1",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.160",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.114",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.49",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1.11",
                            "lessThanOrEqual": "7.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.1",
                            "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": "6.1",
                                    "versionEndExcluding": "6.6.160"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.1",
                                    "versionEndExcluding": "6.12.114"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.1",
                                    "versionEndExcluding": "6.18.49"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.1",
                                    "versionEndExcluding": "7.1.11"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.1",
                                    "versionEndExcluding": "7.2.1"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.1",
                                    "versionEndExcluding": "7.3"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/d0c240f25e654442a72af5ca021a02165ccce638"
                },
                {
                    "url": "https://git.kernel.org/stable/c/9d984451baf768ecd9e1fdad4637b729fcb2c9d5"
                },
                {
                    "url": "https://git.kernel.org/stable/c/e22f4494cc9487d326e5e3067f33dea7c1e442b2"
                },
                {
                    "url": "https://git.kernel.org/stable/c/b6bb334b0e9348887e3e55e1f494b0c3b8fbf59f"
                },
                {
                    "url": "https://git.kernel.org/stable/c/40b6ccf68731809ceb85c6e9f0f8f2ed61c7aa5a"
                },
                {
                    "url": "https://git.kernel.org/stable/c/cd305ee3633a45fcf5f3a5d83f99f3cb77d87b6e"
                }
            ],
            "title": "io_uring: defer eventfd signaling when queued from a wakeup handler",
            "x_generator": {
                "engine": "bippy-1.2.0"
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        }
    }
}