{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-80735",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-08-26T14:34:25.789Z",
        "datePublished": "2026-09-03T08:21:51.344Z",
        "dateUpdated": "2026-09-04T04:58:20.684Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-09-04T04:58:20.684Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\novpn: ensure socket is owned by ovpn before deref sk_user_data\n\nSome subsystems, like BPF SOCKMAP, set sk_user_data without\nactually setting the encap_type.\n\nFor this reason, we must make sure that the type is the\none ovpn expects before dereferencing sk_user_data.\n\nFailing to do so may lead to out-of-bounds reads."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L",
                        "baseScore": 7.3,
                        "baseSeverity": "HIGH"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:L - The flaw is reached only via OVPN_CMD_PEER_NEW genetlink (local sendmsg/netlink syscall) that passes a UDP socket fd into ovpn_socket_new(); BPF SOCKMAP enrollment and ovpn setup are local kernel control paths, not remote packet handling.\nAC:L - An attacker who can use OVPN netlink and BPF SOCKMAP fully controls creating a UDP socket, enrolling it in sockmap (sk_user_data set, encap_type left zero), and issuing PEER_NEW, deterministically hitting the bad cast on each attempt.\nPR:L - All OVPN genetlink commands require GENL_ADMIN_PERM (CAP_NET_ADMIN), and BPF SOCKMAP enrollment needs bpf()/map privileges (CAP_BPF, often plus CAP_NET_ADMIN); both are obtainable by unprivileged users inside permitted user/network namespaces per CNA guidance.\nUI:N - No separate victim action is required; the same local actor creates the ovpn interface, enrolls their UDP socket in BPF SOCKMAP, and sends OVPN_CMD_PEER_NEW to trigger ovpn_socket_new() on that fd.\nS:U - Impact is confined to kernel memory misinterpretation within the host kernel security domain on VPN/offload nodes; it does not cross VM, container runtime, or IOMMU boundaries into another security authority.\nC:H - When sk_user_data points to a BPF sk_psock (or similar non-ovpn owner) but encap_type is zero, ovpn_socket_new() casts it to struct ovpn_socket and reads ovpn_sock->ovpn, a type-confused out-of-bounds read of kernel memory per CNA OOB-read guidance.\nI:H - This is type confusion between foreign sk_user_data objects and struct ovpn_socket; CNA guidance rates type confusion High, and a mistaken ovpn_sock->ovpn match could drive ovpn_socket_hold() against the wrong layout, corrupting refcount-adjacent kernel fields.\nA:L - The common path returns -EBUSY after the misread comparison, but the confused read and any mistaken hold can still provoke WARN/KASAN faults or refcount corruption on VPN gateways running ovpn offload with BPF sockmap, giving at least Low availability impact when uncertain."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/net/ovpn/socket.c"
                    ],
                    "versions": [
                        {
                            "version": "f6226ae7a0cd47aaa9175aca6a1e19600f884cbf",
                            "lessThan": "61fb3cca40ff938671474f4a16adb908c19032d7",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "f6226ae7a0cd47aaa9175aca6a1e19600f884cbf",
                            "lessThan": "43a31142e1d22b3cf5490bd94a94db7196901734",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "f6226ae7a0cd47aaa9175aca6a1e19600f884cbf",
                            "lessThan": "59aed1eb60d70678a53acccb0cb337a26ce6680e",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/net/ovpn/socket.c"
                    ],
                    "versions": [
                        {
                            "version": "6.16",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.16",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.45",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1.9",
                            "lessThanOrEqual": "7.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
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                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                                    "versionEndExcluding": "6.18.45"
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                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.16",
                                    "versionEndExcluding": "7.1.9"
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                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.16",
                                    "versionEndExcluding": "7.2"
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            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/61fb3cca40ff938671474f4a16adb908c19032d7"
                },
                {
                    "url": "https://git.kernel.org/stable/c/43a31142e1d22b3cf5490bd94a94db7196901734"
                },
                {
                    "url": "https://git.kernel.org/stable/c/59aed1eb60d70678a53acccb0cb337a26ce6680e"
                }
            ],
            "title": "ovpn: ensure socket is owned by ovpn before deref sk_user_data",
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}