{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2"
            },
            {
              "fixed": "18899e2e4023369a8f7739c2255a59a9748d8d17"
            },
            {
              "fixed": "88c804847dd87dc613b771b392ccecdb94725032"
            },
            {
              "fixed": "3b12d3967e96f1b7b977d9fc352ae29a1b299a82"
            },
            {
              "fixed": "17b2a1eb97fdb2a2cbaeab3b146b26797ea9311f"
            },
            {
              "fixed": "1f73253add8365d0dad0a4f421acaa8c21d20cef"
            },
            {
              "fixed": "d9f96bc2d822501f84d1caa6275a2c6b316ca2c4"
            },
            {
              "fixed": "899650bbf985b7bfd2a7b808357df9b16e6d6959"
            },
            {
              "fixed": "9ed55f3dbef4f4adfe65eb03b0c35c53229a8490"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.12"
            },
            {
              "fixed": "5.10.271"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.222"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.189"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.158"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.112"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.54"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98276.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: lock the socket in sock_gettstamp()\n\nsk-\u003esk_flags must only be changed while holding the socket lock,\nbecause sock_set_flag() and sock_reset_flag() use non atomic\noperations (__set_bit() and __clear_bit()).\n\nsock_gettstamp() is one of the last places where a bit of sk-\u003esk_flags\nis changed from a syscall without owning the socket lock, through\nsock_enable_timestamp(sk, SOCK_TIMESTAMP).\n\nsk_set_memalloc() and sk_clear_memalloc() also change sk-\u003esk_flags\nwithout the socket lock, but their callers (nbd, iscsi_tcp, nvme-tcp,\nsunrpc, wireguard) need a careful audit, this will be addressed in a\nseparate patch.\n\nJungwoo Lee and Wongi Lee reported an UDP socket use-after-free\ncaused by this bug: a SIOCGSTAMPNS_NEW ioctl racing with bind()\ncan cancel the SOCK_RCU_FREE bit that udp_lib_get_port() just set,\nbecause both threads perform a read-modify-write on the same word.\n\n  CPU 0 (bind)                        CPU 1 (SIOCGSTAMPNS_NEW)\n  --------------------------------    ----------------------------\n  read sk_flags = F                   read sk_flags = F\n  compute F | BIT(SOCK_RCU_FREE)      compute F | BIT(SOCK_TIMESTAMP)\n  store F | BIT(SOCK_RCU_FREE)\n  sk_add_node_rcu(sk, ...)\n                                      store F | BIT(SOCK_TIMESTAMP)\n\nAfter the lost update, SOCK_RCU_FREE is clear while the socket is\nvisible to lockless UDP receive lookups. sk_destruct() then frees\nthe socket immediately instead of waiting for a RCU grace period,\nwhile the receive path still holds a reference-less pointer to it:\n\n BUG: KASAN: slab-use-after-free in ipv4_pktinfo_prepare+0x30/0x410\n Read of size 8 at addr ffff888008806610 by task exploit/207\n CPU: 0 UID: 1000 PID: 207 Comm: exploit Not tainted 6.12.95+ #1\n  ipv4_pktinfo_prepare+0x30/0x410\n  udp_queue_rcv_one_skb+0x51c/0x1180\n  udp_unicast_rcv_skb+0x109/0x350\n  ip_protocol_deliver_rcu+0x14b/0x310\n  ip_local_deliver_finish+0x29d/0x390\n  ip_local_deliver+0x24d/0x2a0\n\nOnly grab the socket lock when SOCK_TIMESTAMP has to be set,\nto keep the common case lockless.",
  "id": "CVE-2026-98276",
  "modified": "2026-10-07T02:31:11.681394497Z",
  "published": "2026-10-06T08:45:36.837Z",
  "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/17b2a1eb97fdb2a2cbaeab3b146b26797ea9311f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/18899e2e4023369a8f7739c2255a59a9748d8d17"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1f73253add8365d0dad0a4f421acaa8c21d20cef"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3b12d3967e96f1b7b977d9fc352ae29a1b299a82"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/88c804847dd87dc613b771b392ccecdb94725032"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/899650bbf985b7bfd2a7b808357df9b16e6d6959"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9ed55f3dbef4f4adfe65eb03b0c35c53229a8490"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d9f96bc2d822501f84d1caa6275a2c6b316ca2c4"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98276.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98276"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "net: lock the socket in sock_gettstamp()"
}