{"id":"CVE-2023-53635","revision":"d4e02e1f05cb4dac95fa730241b56054","records":[{"revision":"d4e02e1f05cb4dac95fa730241b56054","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2023-53635","aliases":[],"title":"netfilter: conntrack: fix wrong ct->timeout value","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: conntrack: fix wrong ct->timeout value\n\n(struct nf_conn)->timeout 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->timeout` twice.\n- Get by calling ctnetlink_dump_timeout(). As a result,\n  `nfct_time_stamp` was wrongly subtracted.\n\nCall Trace:\n <TASK>\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->timeout` in __nf_ct_set_timeout().\n- Getting `ct->timeout` 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.","state":0,"publishedAt":"2025-10-07T15:19:36.973+00:00","modifiedAt":"2026-10-15T21:41:32.395+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"include/net/netfilter/nf_conntrack_core.h\",\n                        \"net/netfilter/nf_conntrack_netlink.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"a4b4766c3cebb4018167e06b863d8e95b7274757\",\n                            \"lessThan\": \"80c5ba0078e20d926d11d0778f9a43902664ebf0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a4b4766c3cebb4018167e06b863d8e95b7274757\",\n                            \"lessThan\": \"ff5e4ac8dd7be7f1faba955c5779a68571eeb0f8\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a4b4766c3cebb4018167e06b863d8e95b7274757\",\n                            \"lessThan\": \"f612ae1ab4793701caf39386fb3b7f4b3ef44e48\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a4b4766c3cebb4018167e06b863d8e95b7274757\",\n                            \"lessThan\": \"73db1b8f2bb6725b7391e85aab41fdf592b3c0c1\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"include/net/netfilter/nf_conntrack_core.h\",\n                        \"net/netfilter/nf_conntrack_netlink.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4.4\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"4.4\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.28\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.2.15\",\n                            \"lessThanOrEqual\": \"6.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.3.2\",\n                            \"lessThanOrEqual\": \"6.3.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.4\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","score":8.2,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/80c5ba0078e20d926d11d0778f9a43902664ebf0","https://git.kernel.org/stable/c/ff5e4ac8dd7be7f1faba955c5779a68571eeb0f8","https://git.kernel.org/stable/c/f612ae1ab4793701caf39386fb3b7f4b3ef44e48","https://git.kernel.org/stable/c/73db1b8f2bb6725b7391e85aab41fdf592b3c0c1"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2023-53635","license":"CVE Program Terms of Use","key":"cve-program:CVE-2023-53635","identifiers":["CVE-2023-53635"]},"retained":false,"historicalAffected":[]}],"coverage":[]}