{"id":"CVE-2023-53635","summary":"netfilter: conntrack: fix wrong ct-\u003etimeout value","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: conntrack: fix wrong ct-\u003etimeout value\n\n(struct nf_conn)-\u003etimeout is an interval before the conntrack\nconfirmed.  After confirmed, it becomes a timestamp.\n\nIt is observed that timeout of an unconfirmed conntrack:\n- Set by calling ctnetlink_change_timeout(). As a result,\n  `nfct_time_stamp` was wrongly added to `ct-\u003etimeout` twice.\n- Get by calling ctnetlink_dump_timeout(). As a result,\n  `nfct_time_stamp` was wrongly subtracted.\n\nCall Trace:\n \u003cTASK\u003e\n dump_stack_lvl\n ctnetlink_dump_timeout\n __ctnetlink_glue_build\n ctnetlink_glue_build\n __nfqnl_enqueue_packet\n nf_queue\n nf_hook_slow\n ip_mc_output\n ? __pfx_ip_finish_output\n ip_send_skb\n ? __pfx_dst_output\n udp_send_skb\n udp_sendmsg\n ? __pfx_ip_generic_getfrag\n sock_sendmsg\n\nSeparate the 2 cases in:\n- Setting `ct-\u003etimeout` in __nf_ct_set_timeout().\n- Getting `ct-\u003etimeout` in ctnetlink_dump_timeout().\n\nPablo appends:\n\nUpdate ctnetlink to set up the timeout _after_ the IPS_CONFIRMED flag is\nset on, otherwise conntrack creation via ctnetlink breaks.\n\nNote that the problem described in this patch occurs since the\nintroduction of the nfnetlink_queue conntrack support, select a\nsufficiently old Fixes: tag for -stable kernel to pick up this fix.","modified":"2026-03-20T12:33:16.212310Z","published":"2025-10-07T15:19:36.973Z","related":["SUSE-SU-2025:4189-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53635.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/73db1b8f2bb6725b7391e85aab41fdf592b3c0c1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/80c5ba0078e20d926d11d0778f9a43902664ebf0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f612ae1ab4793701caf39386fb3b7f4b3ef44e48"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ff5e4ac8dd7be7f1faba955c5779a68571eeb0f8"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53635.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-53635"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"a4b4766c3cebb4018167e06b863d8e95b7274757"},{"fixed":"80c5ba0078e20d926d11d0778f9a43902664ebf0"},{"fixed":"ff5e4ac8dd7be7f1faba955c5779a68571eeb0f8"},{"fixed":"f612ae1ab4793701caf39386fb3b7f4b3ef44e48"},{"fixed":"73db1b8f2bb6725b7391e85aab41fdf592b3c0c1"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2023-53635.json"}}],"schema_version":"1.7.5"}