{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "63ed1aab3d40aa61aaa66819bdce9377ac7f40fa"
            },
            {
              "fixed": "09299addab11857e92eca55cd8ef3350b927c90c"
            },
            {
              "fixed": "e35cb500dd14882f8dee61783fccd1823fd3ab0d"
            },
            {
              "fixed": "f178300e2f56ca9ec2a3a0090608730bbee0af7b"
            },
            {
              "fixed": "26cc0e69cce062cd3aa6fae33074684669c35a71"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.18.0"
            },
            {
              "fixed": "6.12.112"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.55"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98525.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmctp: route: iterate socket tag list in mctp_lookup_prealloc_tag()\n\nWhen a socket transmits a packet with MCTP_TAG_PREALLOC set,\nmctp_lookup_prealloc_tag() iterates over the per-netns \u0026mns-\u003ekeys list\nand matches netid, req_tag, peer_addr, and manual_alloc, without\nchecking whether tmp-\u003esk == \u0026msk-\u003esk. This allows any MCTP socket in the\nsame network namespace to use and consume another socket's preallocated\ntag.\n\nIterate the socket's own tag list (\u0026msk-\u003ekeys via sklist) instead of the\nnamespace-wide \u0026mns-\u003ekeys list in mctp_lookup_prealloc_tag(), ensuring\nthat only tags allocated by msk are matched.\n\nTested in QEMU against Linux 7.3.0-rc3 by allocating a manual tag\n(0x18) on socket A via SIOCMCTPALLOCTAG for peer EID 9 and sending a\n4-byte message with MCTP_TAG_PREALLOC from socket B in the same network\nnamespace. On the unfixed kernel, sendto(sock_b) using socket A's\npreallocated tag succeeds (ret = 4); with this patch applied,\nsendto(sock_b) fails with -ENOENT (errno = 2) while sendto(sock_a)\nsucceeds (ret = 4).",
  "id": "CVE-2026-98525",
  "modified": "2026-10-19T02:30:17.350578106Z",
  "published": "2026-10-18T15:17:43.216Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/09299addab11857e92eca55cd8ef3350b927c90c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/26cc0e69cce062cd3aa6fae33074684669c35a71"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e35cb500dd14882f8dee61783fccd1823fd3ab0d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f178300e2f56ca9ec2a3a0090608730bbee0af7b"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98525.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98525"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "mctp: route: iterate socket tag list in mctp_lookup_prealloc_tag()"
}