{"apiVersion":"1.0","identifier":"CVE-2026-74268","description":"In the Linux kernel, the following vulnerability has been resolved: tcp: clear sock_ops cb flags before force-closing a child socket A child socket inherits the listener-s bpf_sock_ops_cb_flags via sk_clone_lock(). If its setup fails in tcp_v4_syn_recv_sock() / tcp_v6_syn_recv_sock(), the child is freed through put_and_exit, where inet_csk_prepare_forced_close() drops the socket lock and tcp_done() runs without it. If BPF_SOCK_OPS_STATE_CB_FLAG was inherited, tcp_done() -> tcp_set_state() calls tcp_call_bpf(), which expects the lock and trips sock_owned_by_me(): WARNING: include/net/sock.h:1799 at tcp_set_state+0x433/0x550 RIP: 0010:tcp_set_state+0x433/0x550 include/net/sock.h:1799 Call Trace: <IRQ> tcp_done+0xba/0x250 net/ipv4/tcp.c:5095 tcp_v4_syn_recv_sock+0x850/0xa50 net/ipv4/tcp_ipv4.c:1787 tcp_check_req+0xf30/0x1360 net/ipv4/tcp_minisocks.c:926 tcp_v4_rcv+0x1047/0x1b50 net/ipv4/tcp_ipv4.c:2164 </IRQ> The child is freed before it is ever established, so it should run no sock_ops callback. Clear its cb flags in inet_csk_prepare_for_destroy_sock(), the common point for the IPv4, IPv6 and chtls forced-close paths and for the MPTCP ->syn_recv_sock() failure path (dispose_child), which reaches tcp_done() on a child that was never established too.","publishedAt":"2026-08-15T06:22:26","lastModifiedAt":"2026-08-17T06:19:20","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74268","cvssScore":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","epssProbability":0.00598,"riskScore":1.03,"affectedProduct":"Linux kernel","affectedVersions":"unknown","vulnerabilityType":"Kernel","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-74268","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-74268","en":"https://www.redsauce.net/en/cves/CVE-2026-74268","fr":"https://www.redsauce.net/fr/cves/CVE-2026-74268","pt":"https://www.redsauce.net/pt/cves/CVE-2026-74268","de":"https://www.redsauce.net/de/cves/CVE-2026-74268","sk":"https://www.redsauce.net/sk/cves/CVE-2026-74268","el":"https://www.redsauce.net/el/cves/CVE-2026-74268"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-74268"}}