{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "581512a6dc939ef122e49336626ae159f3b8a345"
            },
            {
              "fixed": "72194f65050958e4c8e069adb6c5d89ef81ca197"
            },
            {
              "fixed": "b62e2b2b4a50953ca952f3cd3f77dd62dc50fd5d"
            },
            {
              "fixed": "5d317573f1d48e76cce5fb6250452b6e4102e0fb"
            },
            {
              "fixed": "1e584c304cfb94a759417130b1fc6d30b30c4cce"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.97"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.35"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.0.12"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63970.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nvsock/virtio: bind uarg before filling zerocopy skb\n\nvirtio_transport_send_pkt_info() allocates or reuses the zerocopy uarg\nbefore entering the send loop, but virtio_transport_alloc_skb() still\nfills the skb before it inherits that uarg. When fixed-buffer vectored\nzerocopy hits MAX_SKB_FRAGS, io_sg_from_iter() may partially attach\nmanaged frags and return -EMSGSIZE. The rollback path call kfree_skb()\nto free an skb that carries SKBFL_MANAGED_FRAG_REFS but no uarg, so\nskb_release_data() falls through to ordinary frag unref.\n\nPass the uarg into virtio_transport_alloc_skb() and bind it immediately\nbefore virtio_transport_fill_skb(). This keeps control or no-payload skbs\nuntouched while ensuring success and rollback share one lifetime rule.",
  "id": "CVE-2026-63970",
  "modified": "2026-07-25T03:56:28.277589336Z",
  "published": "2026-07-19T14:55:57.067Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1e584c304cfb94a759417130b1fc6d30b30c4cce"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5d317573f1d48e76cce5fb6250452b6e4102e0fb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/72194f65050958e4c8e069adb6c5d89ef81ca197"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b62e2b2b4a50953ca952f3cd3f77dd62dc50fd5d"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63970.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-63970"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "vsock/virtio: bind uarg before filling zerocopy skb"
}