{"id":"CVE-2026-68117","title":"tipc: clear sock->sk on the failed-insert path in tipc_sk_create()","summary":"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 …","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= efa78f2ae363428525fb4981bb63c555ee79f3c7 < efebc23e9b29e3e5a9e2127dd066929f7f0d315e","Linux >= 833ecd0eae76eadf81d6d747bb5bc992d1151867 < 8d6f26d48e61ef34f1921289401dbf36b10816af","Linux >= 00aff3590fc0a73bddd3b743863c14e76fd35c0c < 82f59aa27f33bd014a7d8739371ab5712d15e33b","Linux >= 00aff3590fc0a73bddd3b743863c14e76fd35c0c < b07d87b31631edb6529e6cdcca790a7489d1250d","Linux >= 00aff3590fc0a73bddd3b743863c14e76fd35c0c < dd29891ed840f6b8d020b759d0dc4a00b1d6e4ea","Linux >= 00aff3590fc0a73bddd3b743863c14e76fd35c0c < 5f5a41a48dbf9eda57b67ce23e548602cf7195a6","Linux >= 00aff3590fc0a73bddd3b743863c14e76fd35c0c < f9596b1566616a8be0592dbceccb6344a7c6f6bb","Linux >= 00aff3590fc0a73bddd3b743863c14e76fd35c0c < ba0533fc163f905fe817cfabdf8ed4058da44800","Linux 638fa20b618b2bbcf86da71231624cc82121a036","Linux 7bc9e7f70bc57d8f02ffea2a42094281effb15ef","Linux ef488669b2652bde5b6ee5a409a5b048a2a50db4","Linux 4919d82f7041157a421ca9bf39a78551d5ad8a1b","Linux 3b2957fc09fe1ac7f07f40dd50dd5f93e3f3a7a2","Linux >= 5.10.132 < 5.10.265","Linux >= 5.15.56 < 5.15.216","Linux >= 4.9.324 < 4.10","Linux >= 4.14.289 < 4.15","Linux >= 4.19.253 < 4.20","Linux >= 5.4.207 < 5.5","Linux >= 5.18.13 < 5.19","Linux 5.19"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total","timestamp":"2026-10-16T15:44:06.454287Z"},"published":"2026-08-10","updated":"2026-10-16","sourceUpdated":"2026-10-16T15:52:57.527Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-68117","references":[{"url":"https://git.kernel.org/stable/c/efebc23e9b29e3e5a9e2127dd066929f7f0d315e"},{"url":"https://git.kernel.org/stable/c/8d6f26d48e61ef34f1921289401dbf36b10816af"},{"url":"https://git.kernel.org/stable/c/82f59aa27f33bd014a7d8739371ab5712d15e33b"},{"url":"https://git.kernel.org/stable/c/b07d87b31631edb6529e6cdcca790a7489d1250d"},{"url":"https://git.kernel.org/stable/c/dd29891ed840f6b8d020b759d0dc4a00b1d6e4ea"},{"url":"https://git.kernel.org/stable/c/5f5a41a48dbf9eda57b67ce23e548602cf7195a6"},{"url":"https://git.kernel.org/stable/c/f9596b1566616a8be0592dbceccb6344a7c6f6bb"},{"url":"https://git.kernel.org/stable/c/ba0533fc163f905fe817cfabdf8ed4058da44800"}],"tags":["cve.org"],"epss":0.00525,"epssPercentile":0.43229,"ingestedAt":"2026-10-16T17:24:46.842Z","slug":"CVE-2026-68117","body":"## Overview\n\nIn 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)\n\n## Affected\n\n- `Linux >= efa78f2ae363428525fb4981bb63c555ee79f3c7 < efebc23e9b29e3e5a9e2127dd066929f7f0d315e`\n- `Linux >= 833ecd0eae76eadf81d6d747bb5bc992d1151867 < 8d6f26d48e61ef34f1921289401dbf36b10816af`\n- `Linux >= 00aff3590fc0a73bddd3b743863c14e76fd35c0c < 82f59aa27f33bd014a7d8739371ab5712d15e33b`\n- `Linux >= 00aff3590fc0a73bddd3b743863c14e76fd35c0c < b07d87b31631edb6529e6cdcca790a7489d1250d`\n- `Linux >= 00aff3590fc0a73bddd3b743863c14e76fd35c0c < dd29891ed840f6b8d020b759d0dc4a00b1d6e4ea`\n- `Linux >= 00aff3590fc0a73bddd3b743863c14e76fd35c0c < 5f5a41a48dbf9eda57b67ce23e548602cf7195a6`\n- `Linux >= 00aff3590fc0a73bddd3b743863c14e76fd35c0c < f9596b1566616a8be0592dbceccb6344a7c6f6bb`\n- `Linux >= 00aff3590fc0a73bddd3b743863c14e76fd35c0c < ba0533fc163f905fe817cfabdf8ed4058da44800`\n- `Linux 638fa20b618b2bbcf86da71231624cc82121a036`\n- `Linux 7bc9e7f70bc57d8f02ffea2a42094281effb15ef`\n- `Linux ef488669b2652bde5b6ee5a409a5b048a2a50db4`\n- `Linux 4919d82f7041157a421ca9bf39a78551d5ad8a1b`\n- `Linux 3b2957fc09fe1ac7f07f40dd50dd5f93e3f3a7a2`\n- `Linux >= 5.10.132 < 5.10.265`\n- `Linux >= 5.15.56 < 5.15.216`\n- `Linux >= 4.9.324 < 4.10`\n- `Linux >= 4.14.289 < 4.15`\n- `Linux >= 4.19.253 < 4.20`\n- `Linux >= 5.4.207 < 5.5`\n- `Linux >= 5.18.13 < 5.19`\n- `Linux 5.19`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}