{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-23254",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-01-13T15:37:45.990Z",
        "datePublished": "2026-03-18T17:41:00.591Z",
        "dateUpdated": "2026-05-23T16:04:21.918Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-05-23T16:04:21.918Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: gro: fix outer network offset\n\nThe udp GRO complete stage assumes that all the packets inserted the RX\nhave the `encapsulation` flag zeroed. Such assumption is not true, as a\nfew H/W NICs can set such flag when H/W offloading the checksum for\nan UDP encapsulated traffic, the tun driver can inject GSO packets with\nUDP encapsulation and the problematic layout can also be created via\na veth based setup.\n\nDue to the above, in the problematic scenarios, udp4_gro_complete() uses\nthe wrong network offset (inner instead of outer) to compute the outer\nUDP header pseudo checksum, leading to csum validation errors later on\nin packet processing.\n\nAddress the issue always clearing the encapsulation flag at GRO completion\ntime. Such flag will be set again as needed for encapsulated packets by\nudp_gro_complete()."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/core/gro.c"
                    ],
                    "versions": [
                        {
                            "version": "af276a5ac8e938c8b058e3e124073cc1e322d98b",
                            "lessThan": "9d40a85138568696387ef04cd004c64612a70874",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "5ef31ea5d053a8f493a772ebad3f3ce82c35d845",
                            "lessThan": "b83557bc6f560433fe5d727e241069f8db5ba709",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "5ef31ea5d053a8f493a772ebad3f3ce82c35d845",
                            "lessThan": "2e5edb69e5d0e23ef248c56fc977039268c77a7b",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "5ef31ea5d053a8f493a772ebad3f3ce82c35d845",
                            "lessThan": "5c2c3c38be396257a6a2e55bd601a12bb9781507",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "dbd9466d323a72e22efe09151253d195d36d3bf6",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "6.6.31",
                            "lessThan": "6.6.124",
                            "status": "affected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.8.10",
                            "lessThan": "6.9",
                            "status": "affected",
                            "versionType": "semver"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/core/gro.c"
                    ],
                    "versions": [
                        {
                            "version": "6.9",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.9",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.124",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.70",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.10",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.19",
                            "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": "6.6.31",
                                    "versionEndExcluding": "6.6.124"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.9",
                                    "versionEndExcluding": "6.12.70"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.9",
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                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.9",
                                    "versionEndExcluding": "6.19"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.8.10"
                                }
                            ]
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                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/9d40a85138568696387ef04cd004c64612a70874"
                },
                {
                    "url": "https://git.kernel.org/stable/c/b83557bc6f560433fe5d727e241069f8db5ba709"
                },
                {
                    "url": "https://git.kernel.org/stable/c/2e5edb69e5d0e23ef248c56fc977039268c77a7b"
                },
                {
                    "url": "https://git.kernel.org/stable/c/5c2c3c38be396257a6a2e55bd601a12bb9781507"
                }
            ],
            "title": "net: gro: fix outer network offset",
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}