{"cve":"CVE-2026-68117","nvd":{"published":"2026-08-10T13:19:56.690","modified":"2026-10-19T21:17:51.760","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntipc: clear sock->sk on the failed-insert path in tipc_sk_create()\n\nWhen tipc_sk_create() fails to insert the new socket (tipc_sk_insert()\nreturns non-zero), its error path frees the sk with sk_free() but leaves\nsock->sk pointing at the freed object:\n\n\tif (tipc_sk_insert(tsk)) {\n\t\tsk_free(sk);\n\t\tpr_warn(\"Socket create failed; port number exhausted\\n\");\n\t\treturn -EINVAL;\n\t}\n\nThis is harmless for plain socket(): the syscall layer clears sock->ops\nbefore releasing, so tipc_release() is never called. It is not harmless\non the accept() path. tipc_accept() creates the pre-allocated child\nsocket with tipc_sk_create(net, new_sock, 0, kern); on failure it leaves\nnew_sock->sk dangling and new_sock->ops non-NULL, and do_accept() then\nfput()s the new file, so __sock_release() -> tipc_release() runs\nlock_sock(new_sock->sk) on the freed sk -- a use-after-free write of the\nsk_lock spinlock.\n\ntipc_release() already guards this exact \"failed accept() releases a\npre-allocated child\" case with \"if (sk == NULL) return 0;\", but the\nguard is bypassed because tipc_sk_create() left sock->sk non-NULL\n(dangling) rather than NULL.\n\nClear sock->sk on the failed-insert path so the existing tipc_release()\nNULL check fires and the use-after-free is avoided.\n\nThe tipc_sk_insert() failure is reached when the per-netns socket\nrhashtable hits its max_size (tsk_rht_params.max_size = 1048576, ~2M\nelements) -- i.e. once a netns holds ~2M TIPC sockets every insert\nreturns -E2BIG.\n\n  BUG: KASAN: slab-use-after-free in lock_sock_nested (net/core/sock.c:3839)\n  Write of size 8 at addr ffff8880047cdc38 by task init/1\n   lock_sock_nested (net/core/sock.c:3839)\n   tipc_release (net/tipc/socket.c:638)\n   __sock_release (net/socket.c:710)\n   sock_close (net/socket.c:1501)\n   __fput (fs/file_table.c:512)\n  Allocated by task 1:\n   sk_alloc (net/core/sock.c:2308)\n   tipc_sk_create (net/tipc/socket.c:487)\n   tipc_accept (net/tipc/socket.c:2744)\n   do_accept (net/socket.c:2034)\n  Freed by task 1:\n   __sk_destruct (net/core/sock.c:2391)\n   tipc_sk_create (net/tipc/socket.c:504)\n   tipc_accept (net/tipc/socket.c:2744)\n   do_accept (net/socket.c:2034)","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-416"],"references":["https://git.kernel.org/stable/c/5f5a41a48dbf9eda57b67ce23e548602cf7195a6","https://git.kernel.org/stable/c/82f59aa27f33bd014a7d8739371ab5712d15e33b","https://git.kernel.org/stable/c/8d6f26d48e61ef34f1921289401dbf36b10816af","https://git.kernel.org/stable/c/b07d87b31631edb6529e6cdcca790a7489d1250d","https://git.kernel.org/stable/c/ba0533fc163f905fe817cfabdf8ed4058da44800"],"products":[],"source":"nvd","synced_at":"2026-10-21T03:56:58.798400159+00:00"},"epss":{"cve":"CVE-2026-68117","score":0.00525,"percentile":0.44231,"date":"2026-10-26"},"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."]}