{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-98374",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-09-25T10:25:14.345Z",
        "datePublished": "2026-10-07T13:01:48.600Z",
        "dateUpdated": "2026-10-19T09:18:26.132Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-10-19T09:18:26.132Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: fix use-after-free of retransmit_skb_hint in tcp_send_synack()\n\nWhen tcp_send_synack() replaces the cloned SYN skb at the head of the\nretransmit queue with a copy, it frees the original with\ntcp_rtx_queue_unlink_and_free() and only repairs tp->highest_sack.\ntp->retransmit_skb_hint keeps pointing at the freed\nskbuff_fclone_cache object.\n\nThe dangling hint is read in tcp_verify_retransmit_hint() and used as\nthe root of the rbtree walk in tcp_xmit_retransmit_queue().  An\nunprivileged TFO client (sendmsg(MSG_FASTOPEN)) can arm the hint with\nan attacker-supplied ICMP fragmentation-needed message, after which a\nsimultaneous open frees the armed SYN skb:\n\n  BUG: KASAN: slab-use-after-free in tcp_mark_skb_lost (net/ipv4/tcp_input.c:1316)\n  Read of size 4 at addr ffff88800604d928 by task swapper/1/0\n  Call Trace:\n   tcp_mark_skb_lost (net/ipv4/tcp_input.c:1316)\n   tcp_simple_retransmit (net/ipv4/tcp_input.c:3158)\n   tcp_v4_err (net/ipv4/tcp_ipv4.c:587)\n\nSync the hint to the copy."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/ipv4/tcp_output.c"
                    ],
                    "versions": [
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "fad6d429651e748365e93ca54645accc212f0018",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "c5b4da1f403a658c1c19766be2b426003ada419f",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "71d45049b0d631dfdbf3c65305f7fca676de023b",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "e3ea71cb1408a013ed4e8a757b815f1a919324bd",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "631aa4cb45099f09e9385dd786bd291c6270bfc4",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "0f87720c7e4bcab07c24888b3cf12bfe857bb90e",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "fe99bbeee5c5dbd3abc30721a8079ced59649d97",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/ipv4/tcp_output.c"
                    ],
                    "versions": [
                        {
                            "version": "5.11",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.11",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.15.222",
                            "lessThanOrEqual": "5.15.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1.189",
                            "lessThanOrEqual": "6.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.158",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.112",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.55",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.9",
                            "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": "5.11",
                                    "versionEndExcluding": "5.15.222"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.11",
                                    "versionEndExcluding": "6.1.189"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.11",
                                    "versionEndExcluding": "6.6.158"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.11",
                                    "versionEndExcluding": "6.12.112"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.11",
                                    "versionEndExcluding": "6.18.55"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.11",
                                    "versionEndExcluding": "7.2.9"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.11",
                                    "versionEndExcluding": "7.3"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/fad6d429651e748365e93ca54645accc212f0018"
                },
                {
                    "url": "https://git.kernel.org/stable/c/c5b4da1f403a658c1c19766be2b426003ada419f"
                },
                {
                    "url": "https://git.kernel.org/stable/c/71d45049b0d631dfdbf3c65305f7fca676de023b"
                },
                {
                    "url": "https://git.kernel.org/stable/c/e3ea71cb1408a013ed4e8a757b815f1a919324bd"
                },
                {
                    "url": "https://git.kernel.org/stable/c/631aa4cb45099f09e9385dd786bd291c6270bfc4"
                },
                {
                    "url": "https://git.kernel.org/stable/c/0f87720c7e4bcab07c24888b3cf12bfe857bb90e"
                },
                {
                    "url": "https://git.kernel.org/stable/c/fe99bbeee5c5dbd3abc30721a8079ced59649d97"
                }
            ],
            "title": "tcp: fix use-after-free of retransmit_skb_hint in tcp_send_synack()",
            "x_generator": {
                "engine": "bippy-1.2.0"
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        }
    }
}