{"cve":"CVE-2026-43252","nvd":{"published":"2026-05-06T12:16:45.873","modified":"2026-06-17T10:49:14.687","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: pm: in-kernel: always set ID as avail when rm endp\n\nSyzkaller managed to find a combination of actions that was generating\nthis warning:\n\n  WARNING: net/mptcp/pm_kernel.c:1074 at __mark_subflow_endp_available net/mptcp/pm_kernel.c:1074 [inline], CPU#1: syz.7.48/2535\n  WARNING: net/mptcp/pm_kernel.c:1074 at mptcp_pm_nl_fullmesh net/mptcp/pm_kernel.c:1446 [inline], CPU#1: syz.7.48/2535\n  WARNING: net/mptcp/pm_kernel.c:1074 at mptcp_pm_nl_set_flags_all net/mptcp/pm_kernel.c:1474 [inline], CPU#1: syz.7.48/2535\n  WARNING: net/mptcp/pm_kernel.c:1074 at mptcp_pm_nl_set_flags+0x5de/0x640 net/mptcp/pm_kernel.c:1538, CPU#1: syz.7.48/2535\n  Modules linked in:\n  CPU: 1 UID: 0 PID: 2535 Comm: syz.7.48 Not tainted 6.18.0-03987-gea5f5e676cf5 #17 PREEMPT(voluntary)\n  Hardware name: QEMU Ubuntu 25.10 PC (i440FX + PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04/01/2014\n  RIP: 0010:__mark_subflow_endp_available net/mptcp/pm_kernel.c:1074 [inline]\n  RIP: 0010:mptcp_pm_nl_fullmesh net/mptcp/pm_kernel.c:1446 [inline]\n  RIP: 0010:mptcp_pm_nl_set_flags_all net/mptcp/pm_kernel.c:1474 [inline]\n  RIP: 0010:mptcp_pm_nl_set_flags+0x5de/0x640 net/mptcp/pm_kernel.c:1538\n  Code: 89 c7 e8 c5 8c 73 fe e9 f7 fd ff ff 49 83 ef 80 e8 b7 8c 73 fe 4c 89 ff be 03 00 00 00 e8 4a 29 e3 fe eb ac e8 a3 8c 73 fe 90 <0f> 0b 90 e9 3d ff ff ff e8 95 8c 73 fe b8 a1 ff ff ff eb 1a e8 89\n  RSP: 0018:ffffc9001535b820 EFLAGS: 00010287\n  netdevsim0: tun_chr_ioctl cmd 1074025677\n  RAX: ffffffff82da294d RBX: 0000000000000001 RCX: 0000000000080000\n  RDX: ffffc900096d0000 RSI: 00000000000006d6 RDI: 00000000000006d7\n  netdevsim0: linktype set to 823\n  RBP: ffff88802cdb2240 R08: 00000000000104ae R09: ffffffffffffffff\n  R10: ffffffff82da27d4 R11: 0000000000000000 R12: 0000000000000000\n  R13: ffff88801246d8c0 R14: ffffc9001535b8b8 R15: ffff88802cdb1800\n  FS:  00007fc6ac5a76c0(0000) GS:ffff8880f90c8000(0000) knlGS:0000000000000000\n  netlink: 'syz.3.50': attribute type 5 has an invalid length.\n  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n  netlink: 1232 bytes leftover after parsing attributes in process `syz.3.50'.\n  CR2: 0000200000010000 CR3: 0000000025b1a000 CR4: 0000000000350ef0\n  Call Trace:\n   <TASK>\n   mptcp_pm_set_flags net/mptcp/pm_netlink.c:277 [inline]\n   mptcp_pm_nl_set_flags_doit+0x1d7/0x210 net/mptcp/pm_netlink.c:282\n   genl_family_rcv_msg_doit+0x117/0x180 net/netlink/genetlink.c:1115\n   genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]\n   genl_rcv_msg+0x3a8/0x3f0 net/netlink/genetlink.c:1210\n   netlink_rcv_skb+0x16d/0x240 net/netlink/af_netlink.c:2550\n   genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219\n   netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]\n   netlink_unicast+0x3e9/0x4c0 net/netlink/af_netlink.c:1344\n   netlink_sendmsg+0x4ab/0x5b0 net/netlink/af_netlink.c:1894\n   sock_sendmsg_nosec net/socket.c:718 [inline]\n   __sock_sendmsg+0xc9/0xf0 net/socket.c:733\n   ____sys_sendmsg+0x272/0x3b0 net/socket.c:2608\n   ___sys_sendmsg+0x2de/0x320 net/socket.c:2662\n   __sys_sendmsg net/socket.c:2694 [inline]\n   __do_sys_sendmsg net/socket.c:2699 [inline]\n   __se_sys_sendmsg net/socket.c:2697 [inline]\n   __x64_sys_sendmsg+0x110/0x1a0 net/socket.c:2697\n   do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n   do_syscall_64+0xed/0x360 arch/x86/entry/syscall_64.c:94\n   entry_SYSCALL_64_after_hwframe+0x77/0x7f\n  RIP: 0033:0x7fc6adb66f6d\n  Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48\n  RSP: 002b:00007fc6ac5a6ff8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e\n  RAX: ffffffffffffffda RBX: 00007fc6addf5fa0 RCX: 00007fc6adb66f6d\n  RDX: 0000000000048084 RSI: 00002000000002c0 RDI: 000000000000000e\n  RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000\n  R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000\n---truncated---","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-667"],"references":["https://git.kernel.org/stable/c/1b3ff4d88b508b73e2bbddb59356311efb7ba192","https://git.kernel.org/stable/c/4d480efd98e290c445f4ba476e4dcda5624b1aab","https://git.kernel.org/stable/c/7c1d221e475e3d8eb8ed4702392d43f8c5134d1f","https://git.kernel.org/stable/c/7e4d88e36e5d0b8ffda637999cbca64c81701a81","https://git.kernel.org/stable/c/d191101dee25567c2af3b28565f45346c33d65f5"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:33:55.586217763+00:00"},"epss":{"cve":"CVE-2026-43252","score":0.00095,"percentile":0.00591,"date":"2026-10-31"},"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."]}