{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-98049",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-09-25T10:19:56.072Z",
        "datePublished": "2026-09-25T10:23:58.561Z",
        "dateUpdated": "2026-10-21T12:54:16.141Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-10-21T12:54:16.141Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: zero extend the result of an arena 32-bit cmpxchg\n\nbpf_convert_ctx_accesses() rewrites an atomic on an arena pointer from\nBPF_STX | BPF_ATOMIC to BPF_STX | BPF_PROBE_ATOMIC, and it runs before\nbpf_opt_subreg_zext_lo32_rnd_hi32().\n\nThat pass emits an explicit zero extension for a 32-bit cmpxchg even\nwhen bpf_jit_needs_zext() is false. This is done because on some\narchitectures 32-bit cmpxchg requires explicit zero extension for the\ndst register. E.g. on x86-64 'lock cmpxchg' does not change the %eax\nif comparison is successful, while BPF semantics declare that each\noperation on a 32-bit register zero extends it's upper half.\n\nis_cmpxchg_insn() matches BPF_MODE == BPF_ATOMIC only, so an arena\ncmpxchg misses said zero extension adjustment. This patch adjusts\nis_cmpxchg_insn() to match BPF_PROBE_ATOMIC alongside BPF_ATOMIC."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "kernel/bpf/fixups.c"
                    ],
                    "versions": [
                        {
                            "version": "d503a04f8bc0c75dc9db9452d8cc79d748afb752",
                            "lessThan": "1bb1be18263995b159cf5afad3a05500ba6d2a7b",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "d503a04f8bc0c75dc9db9452d8cc79d748afb752",
                            "lessThan": "6bb6ae5ab1beffda51dabf41612f501d07f10fc6",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "d503a04f8bc0c75dc9db9452d8cc79d748afb752",
                            "lessThan": "1c1b476d43a8b6c9bc04600369dd8cc39950d98e",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "d503a04f8bc0c75dc9db9452d8cc79d748afb752",
                            "lessThan": "4814ed6406f3493bd554ad046da5f7fc04833571",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "kernel/bpf/fixups.c"
                    ],
                    "versions": [
                        {
                            "version": "6.10",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.10",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.114",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.57",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.7",
                            "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": "6.10",
                                    "versionEndExcluding": "6.12.114"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.10",
                                    "versionEndExcluding": "6.18.57"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.10",
                                    "versionEndExcluding": "7.2.7"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.10",
                                    "versionEndExcluding": "7.3"
                                }
                            ]
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                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/1bb1be18263995b159cf5afad3a05500ba6d2a7b"
                },
                {
                    "url": "https://git.kernel.org/stable/c/6bb6ae5ab1beffda51dabf41612f501d07f10fc6"
                },
                {
                    "url": "https://git.kernel.org/stable/c/1c1b476d43a8b6c9bc04600369dd8cc39950d98e"
                },
                {
                    "url": "https://git.kernel.org/stable/c/4814ed6406f3493bd554ad046da5f7fc04833571"
                }
            ],
            "title": "bpf: zero extend the result of an arena 32-bit cmpxchg",
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}