{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2025-71128",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-01-13T15:30:19.655Z",
        "datePublished": "2026-01-14T15:07:44.941Z",
        "dateUpdated": "2026-08-05T12:12:14.477Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T12:12:14.477Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nerspan: Initialize options_len before referencing options.\n\nThe struct ip_tunnel_info has a flexible array member named\noptions that is protected by a counted_by(options_len)\nattribute.\n\nThe compiler will use this information to enforce runtime bounds\nchecking deployed by FORTIFY_SOURCE string helpers.\n\nAs laid out in the GCC documentation, the counter must be\ninitialized before the first reference to the flexible array\nmember.\n\nAfter scanning through the files that use struct ip_tunnel_info\nand also refer to options or options_len, it appears the normal\ncase is to use the ip_tunnel_info_opts_set() helper.\n\nSaid helper would initialize options_len properly before copying\ndata into options, however in the GRE ERSPAN code a partial\nupdate is done, preventing the use of the helper function.\n\nBefore this change the handling of ERSPAN traffic in GRE tunnels\nwould cause a kernel panic when the kernel is compiled with\nGCC 15+ and having FORTIFY_SOURCE configured:\n\nmemcpy: detected buffer overflow: 4 byte write of buffer size 0\n\nCall Trace:\n <IRQ>\n __fortify_panic+0xd/0xf\n erspan_rcv.cold+0x68/0x83\n ? ip_route_input_slow+0x816/0x9d0\n gre_rcv+0x1b2/0x1c0\n gre_rcv+0x8e/0x100\n ? raw_v4_input+0x2a0/0x2b0\n ip_protocol_deliver_rcu+0x1ea/0x210\n ip_local_deliver_finish+0x86/0x110\n ip_local_deliver+0x65/0x110\n ? ip_rcv_finish_core+0xd6/0x360\n ip_rcv+0x186/0x1a0\n\nReported-at: https://launchpad.net/bugs/2129580"
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                        "baseScore": 7.5,
                        "baseSeverity": "HIGH"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:N - IPv4 or IPv6 ERSPAN is carried over routable GRE/IP, allowing a remote attacker to send packets directly to an enabled collect-metadata ERSPAN endpoint.\nAC:L - Once the affected GCC 15+ FORTIFY build and metadata-mode endpoint exist, one well-formed packet deterministically triggers the failure without a race or heap-layout requirement.\nPR:N - Creating the endpoint requires CAP_NET_ADMIN, but the packet-processing path has no capability or authentication gate. A collect-metadata tunnel acts as a wildcard endpoint and accepts packets from unauthenticated peers.\nUI:N - Receiving the attacker-supplied packet triggers the vulnerability without any victim action.\nS:U - The resulting kernel failure affects resources governed by the same host-kernel security authority and does not cross a VM or comparable boundary.\nC:N - The allocation includes the complete ERSPAN metadata buffer, and FORTIFY invokes BUG() before the allegedly overflowing copy; no out-of-bounds read or disclosure primitive exists.\nI:N - The defect does not perform an out-of-bounds write: the destination is physically large enough, and the erroneous runtime bounds check stops execution before memcpy.\nA:H - The zero dynamic bound reaches __fortify_panic and BUG() in the receive softirq, producing a repeatable kernel oops or panic and system-wide service loss."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/ipv4/ip_gre.c",
                        "net/ipv6/ip6_gre.c"
                    ],
                    "versions": [
                        {
                            "version": "bb5e62f2d547c4de6d1b144cbce2373a76c33f18",
                            "lessThan": "b282b2a9eed848587c1348abdd5d83fa346a2743",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "bb5e62f2d547c4de6d1b144cbce2373a76c33f18",
                            "lessThan": "35ddf66c65eff93fff91406756ba273600bf61a3",
                            "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/ip_gre.c",
                        "net/ipv6/ip6_gre.c"
                    ],
                    "versions": [
                        {
                            "version": "6.15",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.15",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.4",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.19",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
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                    "nodes": [
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                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
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                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.15",
                                    "versionEndExcluding": "6.18.4"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.15",
                                    "versionEndExcluding": "6.19"
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            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/b282b2a9eed848587c1348abdd5d83fa346a2743"
                },
                {
                    "url": "https://git.kernel.org/stable/c/35ddf66c65eff93fff91406756ba273600bf61a3"
                }
            ],
            "title": "erspan: Initialize options_len before referencing options.",
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