{"cve":"CVE-2024-36927","nvd":{"published":"2024-05-30T16:15:15.957","modified":"2026-10-15T01:18:25.447","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: Fix uninit-value access in __ip_make_skb()\n\nKMSAN reported uninit-value access in __ip_make_skb() [1].  __ip_make_skb()\ntests HDRINCL to know if the skb has icmphdr. However, HDRINCL can cause a\nrace condition. If calling setsockopt(2) with IP_HDRINCL changes HDRINCL\nwhile __ip_make_skb() is running, the function will access icmphdr in the\nskb even if it is not included. This causes the issue reported by KMSAN.\n\nCheck FLOWI_FLAG_KNOWN_NH on fl4->flowi4_flags instead of testing HDRINCL\non the socket.\n\nAlso, fl4->fl4_icmp_type and fl4->fl4_icmp_code are not initialized. These\nare union in struct flowi4 and are implicitly initialized by\nflowi4_init_output(), but we should not rely on specific union layout.\n\nInitialize these explicitly in raw_sendmsg().\n\n[1]\nBUG: KMSAN: uninit-value in __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481\n __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481\n ip_finish_skb include/net/ip.h:243 [inline]\n ip_push_pending_frames+0x4c/0x5c0 net/ipv4/ip_output.c:1508\n raw_sendmsg+0x2381/0x2690 net/ipv4/raw.c:654\n inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851\n sock_sendmsg_nosec net/socket.c:730 [inline]\n __sock_sendmsg+0x274/0x3c0 net/socket.c:745\n __sys_sendto+0x62c/0x7b0 net/socket.c:2191\n __do_sys_sendto net/socket.c:2203 [inline]\n __se_sys_sendto net/socket.c:2199 [inline]\n __x64_sys_sendto+0x130/0x200 net/socket.c:2199\n do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x6d/0x75\n\nUninit was created at:\n slab_post_alloc_hook mm/slub.c:3804 [inline]\n slab_alloc_node mm/slub.c:3845 [inline]\n kmem_cache_alloc_node+0x5f6/0xc50 mm/slub.c:3888\n kmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:577\n __alloc_skb+0x35a/0x7c0 net/core/skbuff.c:668\n alloc_skb include/linux/skbuff.h:1318 [inline]\n __ip_append_data+0x49ab/0x68c0 net/ipv4/ip_output.c:1128\n ip_append_data+0x1e7/0x260 net/ipv4/ip_output.c:1365\n raw_sendmsg+0x22b1/0x2690 net/ipv4/raw.c:648\n inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851\n sock_sendmsg_nosec net/socket.c:730 [inline]\n __sock_sendmsg+0x274/0x3c0 net/socket.c:745\n __sys_sendto+0x62c/0x7b0 net/socket.c:2191\n __do_sys_sendto net/socket.c:2203 [inline]\n __se_sys_sendto net/socket.c:2199 [inline]\n __x64_sys_sendto+0x130/0x200 net/socket.c:2199\n do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x6d/0x75\n\nCPU: 1 PID: 15709 Comm: syz-executor.7 Not tainted 6.8.0-11567-gb3603fcb79b1 #25\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","score":4.7},"cwes":["CWE-362","CWE-908"],"references":["https://git.kernel.org/stable/c/20d3eb00ab81462d554ac6d09691b8d9aa5a5741","https://git.kernel.org/stable/c/55bf541e018b76b3750cb6c6ea18c46e1ac5562e","https://git.kernel.org/stable/c/5db08343ddb1b239320612036c398e4e1bb52818","https://git.kernel.org/stable/c/88c66f1879f322f11de34d37b2d3d87497afdcb6","https://git.kernel.org/stable/c/f5c603ad4e6fcf42f84053e882ebe20184bb309e"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:51:20.603330631+00:00"},"epss":{"cve":"CVE-2024-36927","score":0.00178,"percentile":0.07315,"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."]}