{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "d7b0e37c1ac152905b18a5b9506179091a35b0b6"
            },
            {
              "fixed": "8de4f665d0febfb92803dece377791a563fc7041"
            },
            {
              "fixed": "8145b432136285e01091815b48ceb2dae261f262"
            },
            {
              "fixed": "1951bffbc6493ec34cff3956b29d4bc6606904a6"
            },
            {
              "fixed": "647b19e5cc145a2f1f685ae8ff3805a17356888c"
            },
            {
              "fixed": "472e9d7c0d5b03be3ff91ff941f57da822b031bc"
            },
            {
              "fixed": "3bfb96d9bc6a7ed0b99c7db329cc2e22a28d84bb"
            },
            {
              "fixed": "ce5aa8084329351086894aa34d77e40301d5bd3d"
            },
            {
              "fixed": "9d160b35cc34a2ba8229d07651468a7848325135"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.18.0"
            },
            {
              "fixed": "5.10.261"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.212"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.178"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.145"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.97"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.40"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64541.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: fix UAF in smc_cdc_rx_handler() by pinning the socket\n\nsmc_cdc_rx_handler() looks up the connection by token under the link\ngroup's conns_lock, drops the lock, and then dereferences conn and the\nsmc_sock derived from it, ending in sock_hold(\u0026smc-\u003esk) inside\nsmc_cdc_msg_recv(). No reference is held across the lock release.\n\nThe only reference pinning the socket while the connection is\ndiscoverable in the link group is taken in smc_lgr_register_conn()\n(sock_hold) and dropped in __smc_lgr_unregister_conn() (sock_put), both\nunder conns_lock. Once the handler drops conns_lock, a concurrent\nclose() -\u003e smc_release() -\u003e smc_conn_free() -\u003e smc_lgr_unregister_conn()\ncan drop that reference and free the smc_sock, so the handler's later\nsock_hold() runs on freed memory:\n\n  WARNING: lib/refcount.c:25 at refcount_warn_saturate\n  Workqueue: rxe_wq do_work\n   refcount_warn_saturate (lib/refcount.c:25)\n   smc_cdc_msg_recv (net/smc/smc_cdc.c:430)\n   smc_cdc_rx_handler (net/smc/smc_cdc.c:502)\n   smc_wr_rx_tasklet_fn (net/smc/smc_wr.c:445)\n   tasklet_action_common (kernel/softirq.c:938)\n   handle_softirqs (kernel/softirq.c:622)\n  Kernel panic - not syncing: panic_on_warn set\n\nOnly SMC-R is affected. The SMC-D receive tasklet is stopped by\ntasklet_kill(\u0026conn-\u003erx_tsklet) in smc_conn_free() before the connection\nis unregistered, so it cannot run concurrently with the free.\n\nTake the socket reference while still holding conns_lock, so the\nregistration reference can no longer be the last one, and drop it once\nthe handler is done.",
  "id": "CVE-2026-64541",
  "modified": "2026-07-28T03:55:59.250043315Z",
  "published": "2026-07-27T20:10:34.439Z",
  "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/1951bffbc6493ec34cff3956b29d4bc6606904a6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3bfb96d9bc6a7ed0b99c7db329cc2e22a28d84bb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/472e9d7c0d5b03be3ff91ff941f57da822b031bc"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/647b19e5cc145a2f1f685ae8ff3805a17356888c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8145b432136285e01091815b48ceb2dae261f262"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8de4f665d0febfb92803dece377791a563fc7041"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9d160b35cc34a2ba8229d07651468a7848325135"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ce5aa8084329351086894aa34d77e40301d5bd3d"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64541.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64541"
    }
  ],
  "schema_version": "1.8.0",
  "summary": "net/smc: fix UAF in smc_cdc_rx_handler() by pinning the socket"
}