{"cve":"CVE-2021-47597","nvd":{"published":"2024-06-19T15:15:54.290","modified":"2026-06-17T04:17:50.973","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ninet_diag: fix kernel-infoleak for UDP sockets\n\nKMSAN reported a kernel-infoleak [1], that can exploited\nby unpriv users.\n\nAfter analysis it turned out UDP was not initializing\nr->idiag_expires. Other users of inet_sk_diag_fill()\nmight make the same mistake in the future, so fix this\nin inet_sk_diag_fill().\n\n[1]\nBUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:121 [inline]\nBUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:156 [inline]\nBUG: KMSAN: kernel-infoleak in _copy_to_iter+0x69d/0x25c0 lib/iov_iter.c:670\n instrument_copy_to_user include/linux/instrumented.h:121 [inline]\n copyout lib/iov_iter.c:156 [inline]\n _copy_to_iter+0x69d/0x25c0 lib/iov_iter.c:670\n copy_to_iter include/linux/uio.h:155 [inline]\n simple_copy_to_iter+0xf3/0x140 net/core/datagram.c:519\n __skb_datagram_iter+0x2cb/0x1280 net/core/datagram.c:425\n skb_copy_datagram_iter+0xdc/0x270 net/core/datagram.c:533\n skb_copy_datagram_msg include/linux/skbuff.h:3657 [inline]\n netlink_recvmsg+0x660/0x1c60 net/netlink/af_netlink.c:1974\n sock_recvmsg_nosec net/socket.c:944 [inline]\n sock_recvmsg net/socket.c:962 [inline]\n sock_read_iter+0x5a9/0x630 net/socket.c:1035\n call_read_iter include/linux/fs.h:2156 [inline]\n new_sync_read fs/read_write.c:400 [inline]\n vfs_read+0x1631/0x1980 fs/read_write.c:481\n ksys_read+0x28c/0x520 fs/read_write.c:619\n __do_sys_read fs/read_write.c:629 [inline]\n __se_sys_read fs/read_write.c:627 [inline]\n __x64_sys_read+0xdb/0x120 fs/read_write.c:627\n do_syscall_x64 arch/x86/entry/common.c:51 [inline]\n do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n\nUninit was created at:\n slab_post_alloc_hook mm/slab.h:524 [inline]\n slab_alloc_node mm/slub.c:3251 [inline]\n __kmalloc_node_track_caller+0xe0c/0x1510 mm/slub.c:4974\n kmalloc_reserve net/core/skbuff.c:354 [inline]\n __alloc_skb+0x545/0xf90 net/core/skbuff.c:426\n alloc_skb include/linux/skbuff.h:1126 [inline]\n netlink_dump+0x3d5/0x16a0 net/netlink/af_netlink.c:2245\n __netlink_dump_start+0xd1c/0xee0 net/netlink/af_netlink.c:2370\n netlink_dump_start include/linux/netlink.h:254 [inline]\n inet_diag_handler_cmd+0x2e7/0x400 net/ipv4/inet_diag.c:1343\n sock_diag_rcv_msg+0x24a/0x620\n netlink_rcv_skb+0x447/0x800 net/netlink/af_netlink.c:2491\n sock_diag_rcv+0x63/0x80 net/core/sock_diag.c:276\n netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]\n netlink_unicast+0x1095/0x1360 net/netlink/af_netlink.c:1345\n netlink_sendmsg+0x16f3/0x1870 net/netlink/af_netlink.c:1916\n sock_sendmsg_nosec net/socket.c:704 [inline]\n sock_sendmsg net/socket.c:724 [inline]\n sock_write_iter+0x594/0x690 net/socket.c:1057\n do_iter_readv_writev+0xa7f/0xc70\n do_iter_write+0x52c/0x1500 fs/read_write.c:851\n vfs_writev fs/read_write.c:924 [inline]\n do_writev+0x63f/0xe30 fs/read_write.c:967\n __do_sys_writev fs/read_write.c:1040 [inline]\n __se_sys_writev fs/read_write.c:1037 [inline]\n __x64_sys_writev+0xe5/0x120 fs/read_write.c:1037\n do_syscall_x64 arch/x86/entry/common.c:51 [inline]\n do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n\nBytes 68-71 of 312 are uninitialized\nMemory access of size 312 starts at ffff88812ab54000\nData copied to user address 0000000020001440\n\nCPU: 1 PID: 6365 Comm: syz-executor801 Not tainted 5.16.0-rc3-syzkaller #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","score":5.5},"cwes":["CWE-908"],"references":["https://git.kernel.org/stable/c/3a4f6dba1eb98101abc012ef968a8b10dac1ce50","https://git.kernel.org/stable/c/71ddeac8cd1d217744a0e060ff520e147c9328d1","https://git.kernel.org/stable/c/7b5596e531253ce84213d9daa7120b71c9d83198","https://git.kernel.org/stable/c/e5d28205bf1de7082d904ed277ceb2db2879e302","https://git.kernel.org/stable/c/3a4f6dba1eb98101abc012ef968a8b10dac1ce50"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:52:00.836172422+00:00"},"epss":{"cve":"CVE-2021-47597","score":0.00254,"percentile":0.16931,"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."]}