{"cve":"CVE-2021-47459","nvd":{"published":"2024-05-22T07:15:10.863","modified":"2026-08-04T10:17:04.430","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: j1939: j1939_netdev_start(): fix UAF for rx_kref of j1939_priv\n\nIt will trigger UAF for rx_kref of j1939_priv as following.\n\n        cpu0                                    cpu1\nj1939_sk_bind(socket0, ndev0, ...)\nj1939_netdev_start\n                                        j1939_sk_bind(socket1, ndev0, ...)\n                                        j1939_netdev_start\nj1939_priv_set\n                                        j1939_priv_get_by_ndev_locked\nj1939_jsk_add\n.....\nj1939_netdev_stop\nkref_put_lock(&priv->rx_kref, ...)\n                                        kref_get(&priv->rx_kref, ...)\n                                        REFCOUNT_WARN(\"addition on 0;...\")\n\n====================================================\nrefcount_t: addition on 0; use-after-free.\nWARNING: CPU: 1 PID: 20874 at lib/refcount.c:25 refcount_warn_saturate+0x169/0x1e0\nRIP: 0010:refcount_warn_saturate+0x169/0x1e0\nCall Trace:\n j1939_netdev_start+0x68b/0x920\n j1939_sk_bind+0x426/0xeb0\n ? security_socket_bind+0x83/0xb0\n\nThe rx_kref's kref_get() and kref_put() should use j1939_netdev_lock to\nprotect.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-416"],"references":["https://git.kernel.org/stable/c/6e8811707e2df0c6ba920f0cad3a3bca7b42132f","https://git.kernel.org/stable/c/864e77771a24c877aaf53aee019f78619cbcd668","https://git.kernel.org/stable/c/a0e47d2833b4f65e6c799f28c6b636d36b8b936d","https://git.kernel.org/stable/c/d9d52a3ebd284882f5562c88e55991add5d01586","https://git.kernel.org/stable/c/6e8811707e2df0c6ba920f0cad3a3bca7b42132f"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:50:30.954589733+00:00"},"epss":{"cve":"CVE-2021-47459","score":0.00226,"percentile":0.13413,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}