{"cve":"CVE-2025-21862","nvd":{"published":"2025-03-12T10:15:19.253","modified":"2026-10-15T02:17:39.560","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrop_monitor: fix incorrect initialization order\n\nSyzkaller reports the following bug:\n\nBUG: spinlock bad magic on CPU#1, syz-executor.0/7995\n lock: 0xffff88805303f3e0, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0\nCPU: 1 PID: 7995 Comm: syz-executor.0 Tainted: G            E     5.10.209+ #1\nHardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020\nCall Trace:\n __dump_stack lib/dump_stack.c:77 [inline]\n dump_stack+0x119/0x179 lib/dump_stack.c:118\n debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline]\n do_raw_spin_lock+0x1f6/0x270 kernel/locking/spinlock_debug.c:112\n __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:117 [inline]\n _raw_spin_lock_irqsave+0x50/0x70 kernel/locking/spinlock.c:159\n reset_per_cpu_data+0xe6/0x240 [drop_monitor]\n net_dm_cmd_trace+0x43d/0x17a0 [drop_monitor]\n genl_family_rcv_msg_doit+0x22f/0x330 net/netlink/genetlink.c:739\n genl_family_rcv_msg net/netlink/genetlink.c:783 [inline]\n genl_rcv_msg+0x341/0x5a0 net/netlink/genetlink.c:800\n netlink_rcv_skb+0x14d/0x440 net/netlink/af_netlink.c:2497\n genl_rcv+0x29/0x40 net/netlink/genetlink.c:811\n netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline]\n netlink_unicast+0x54b/0x800 net/netlink/af_netlink.c:1348\n netlink_sendmsg+0x914/0xe00 net/netlink/af_netlink.c:1916\n sock_sendmsg_nosec net/socket.c:651 [inline]\n __sock_sendmsg+0x157/0x190 net/socket.c:663\n ____sys_sendmsg+0x712/0x870 net/socket.c:2378\n ___sys_sendmsg+0xf8/0x170 net/socket.c:2432\n __sys_sendmsg+0xea/0x1b0 net/socket.c:2461\n do_syscall_64+0x30/0x40 arch/x86/entry/common.c:46\n entry_SYSCALL_64_after_hwframe+0x62/0xc7\nRIP: 0033:0x7f3f9815aee9\nCode: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 b0 ff ff ff f7 d8 64 89 01 48\nRSP: 002b:00007f3f972bf0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e\nRAX: ffffffffffffffda RBX: 00007f3f9826d050 RCX: 00007f3f9815aee9\nRDX: 0000000020000000 RSI: 0000000020001300 RDI: 0000000000000007\nRBP: 00007f3f981b63bd R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000\nR13: 000000000000006e R14: 00007f3f9826d050 R15: 00007ffe01ee6768\n\nIf drop_monitor is built as a kernel module, syzkaller may have time\nto send a netlink NET_DM_CMD_START message during the module loading.\nThis will call the net_dm_monitor_start() function that uses\na spinlock that has not yet been initialized.\n\nTo fix this, let's place resource initialization above the registration\nof a generic netlink family.\n\nFound by InfoTeCS on behalf of Linux Verification Center\n(linuxtesting.org) with Syzkaller.","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-908"],"references":["https://git.kernel.org/stable/c/07b598c0e6f06a0f254c88dafb4ad50f8a8c6eea","https://git.kernel.org/stable/c/0efa6c42f81c60d8f72ba7f5ed8d4fec8c526282","https://git.kernel.org/stable/c/219a47d0e6195bd202f22855e35f25bd15bc4d58","https://git.kernel.org/stable/c/29f9cdcab3d96d5207a5c92b52c40ad75e5915d8","https://git.kernel.org/stable/c/6e9e0f224ffd8b819da3ea247dda404795fdd182"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:00:17.429720821+00:00"},"epss":{"cve":"CVE-2025-21862","score":0.00252,"percentile":0.16458,"date":"2026-10-25"},"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."]}