{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-68142",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-68142"
  ],
  "published": "2026-08-10T12:08:00Z",
  "summary": "geneve: require CAP_NET_ADMIN in the device netns for changelink",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ngeneve: require CAP_NET_ADMIN in the device netns for changelink\n\nA tunnel changelink() operates on at most two netns, dev_net(dev) and\nthe sticky underlay netns geneve->net. They differ once the device is\ncreated in or moved to a netns other than the one the request runs in.\nThe rtnl changelink path checks CAP_NET_ADMIN only against dev_net(dev),\nso a caller privileged there but not in geneve->net can rewrite a geneve\ndevice whose underlay lives in geneve->net.\n\ngeneve_changelink() applies the new configuration against geneve->net:\ngeneve_link_config() and the geneve_quiesce()/geneve_unquiesce() pair\nreopen the underlay sockets in that netns (geneve_sock_add() uses\ngeneve->net), so the same reasoning as the tunnel changelink series\napplies here.\n\nGate geneve_changelink() with rtnl_dev_link_net_capable(), at the top of\nthe op before any attribute is parsed, matching ipgre_changelink() and\nthe rest of the \"require CAP_NET_ADMIN in the device netns for\nchangelink\" series.\n\nFound by 0sec automated security-research tooling (https://0sec.ai).",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.183",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-68142"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/a5522963c57f12df5f9db804ebfc472b58eef0ae"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/278c6a31ee27c931c722202c8c06cc3253923254"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/11a7d989d00160481a273eb4f7f05f64b5a6ffdf"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/2abdacc927c92fa6a9cc8341e8c9b88dcb561553"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9de5518fc1fab583526a8f66b8e505c4864dc60a"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/f8c498585d2a08aa623748353c3e61467b7e9fd2"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/95f45e20f1b2cec13823f0f68060ab4b2261b2c1"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/8efb8f8bbb353b8f2fdf4f37534c6d96c9f69e01"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-19T16:47:12Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 8.8,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - Exploitation requires issuing RTM_NEWLINK changelink over a local rtnetlink socket; geneve_changelink is only reachable from the rtnl configuration path, not from received GENEVE/UDP network packets.\nAC:L - Once a geneve device exists with geneve->net differing from dev_net(dev) (via IFLA_NET_NS_FD migration or IFLA_LINK_NETNSID newlink), a single deterministic netlink changelink bypasses the missing check with no race or memory-layout dependency.\nPR:L - The rtnl entry path requires CAP_NET_ADMIN in dev_net(dev), obtainable by an unprivileged local user inside a user+network namespace via unshare --user --map-root-user --net; no CAP_NET_ADMIN in the sticky underlay netns geneve->net is needed.\nUI:N - The attack is fully programmatic through netlink from the attacker's own process; no victim action such as mounting a filesystem, opening a file, or clicking is required.\nS:C - geneve_changelink applies geneve_link_config() and geneve_quiesce()/geneve_unquiesce() (reopening underlay sockets via geneve_sock_add() in geneve->net) while authorization is checked only against dev_net(dev), crossing into another tenant's or the host's network namespace.\nC:H - An attacker can set IFLA_GENEVE_REMOTE/REMOTE6 to redirect encapsulated overlay traffic to an attacker-controlled endpoint and read tunneled payloads from the victim underlay netns.\nI:H - Unauthorized changelink mutates live tunnel remote endpoint, TTL/TOS/DF/label, and MTU in geneve->net, enabling redirection and injection of overlay traffic without authorization in that namespace.\nA:H - geneve_quiesce() drops in-flight tunnel traffic and rewriting the remote endpoint or MTU breaks production GENEVE overlays (Kubernetes/OVN/cloud SDN), causing sustained loss of connectivity for dependent services."
    }
  }
}