{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2024-41041", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2024-41041", "idYear": 2024, "status": "PUBLISHED", "publishedAt": "2024-07-29T14:31:54.647Z", "updatedAt": "2026-08-05T11:34:56.026Z", "importedAt": "2026-10-24T01:57:16.009Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "udp: Set SOCK_RCU_FREE earlier in udp_lib_get_port().", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nudp: Set SOCK_RCU_FREE earlier in udp_lib_get_port().\n\nsyzkaller triggered the warning [0] in udp_v4_early_demux().\n\nIn udp_v[46]_early_demux() and sk_lookup(), we do not touch the refcount\nof the looked-up sk and use sock_pfree() as skb->destructor, so we check\nSOCK_RCU_FREE to ensure that the sk is safe to access during the RCU grace\nperiod.\n\nCurrently, SOCK_RCU_FREE is flagged for a bound socket after being put\ninto the hash table. Moreover, the SOCK_RCU_FREE check is done too early\nin udp_v[46]_early_demux() and sk_lookup(), so there could be a small race\nwindow:\n\n CPU1 CPU2\n ---- ----\n udp_v4_early_demux() udp_lib_get_port()\n | |- hlist_add_head_rcu()\n |- sk = __udp4_lib_demux_lookup() |\n |- DEBUG_NET_WARN_ON_ONCE(sk_is_refcounted(sk));\n `- sock_set_flag(sk, SOCK_RCU_FREE)\n\nWe had the same bug in TCP and fixed it in commit 871019b22d1b (\"net:\nset SOCK_RCU_FREE before inserting socket into hashtable\").\n\nLet's apply the same fix for UDP.\n\n[0]:\nWARNING: CPU: 0 PID: 11198 at net/ipv4/udp.c:2599 udp_v4_early_demux+0x481/0xb70 net/ipv4/udp.c:2599\nModules linked in:\nCPU: 0 PID: 11198 Comm: syz-executor.1 Not tainted 6.9.0-g93bda33046e7 #13\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014\nRIP: 0010:udp_v4_early_demux+0x481/0xb70 net/ipv4/udp.c:2599\nCode: c5 7a 15 fe bb 01 00 00 00 44 89 e9 31 ff d3 e3 81 e3 bf ef ff ff 89 de e8 2c 74 15 fe 85 db 0f 85 02 06 00 00 e8 9f 7a 15 fe <0f> 0b e8 98 7a 15 fe 49 8d 7e 60 e8 4f 39 2f fe 49 c7 46 60 20 52\nRSP: 0018:ffffc9000ce3fa58 EFLAGS: 00010293\nRAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8318c92c\nRDX: ffff888036ccde00 RSI: ffffffff8318c2f1 RDI: 0000000000000001\nRBP: ffff88805a2dd6e0 R08: 0000000000000001 R09: 0000000000000000\nR10: 0000000000000000 R11: 0001ffffffffffff R12: ffff88805a2dd680\nR13: 0000000000000007 R14: ffff88800923f900 R15: ffff88805456004e\nFS: 00007fc449127640(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000\nCS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00007fc449126e38 CR3: 000000003de4b002 CR4: 0000000000770ef0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600\nPKRU: 55555554\nCall Trace:\n \n ip_rcv_finish_core.constprop.0+0xbdd/0xd20 net/ipv4/ip_input.c:349\n ip_rcv_finish+0xda/0x150 net/ipv4/ip_input.c:447\n NF_HOOK include/linux/netfilter.h:314 [inline]\n NF_HOOK include/linux/netfilter.h:308 [inline]\n ip_rcv+0x16c/0x180 net/ipv4/ip_input.c:569\n __netif_receive_skb_one_core+0xb3/0xe0 net/core/dev.c:5624\n __netif_receive_skb+0x21/0xd0 net/core/dev.c:5738\n netif_receive_skb_internal net/core/dev.c:5824 [inline]\n netif_receive_skb+0x271/0x300 net/core/dev.c:5884\n tun_rx_batched drivers/net/tun.c:1549 [inline]\n tun_get_user+0x24db/0x2c50 drivers/net/tun.c:2002\n tun_chr_write_iter+0x107/0x1a0 drivers/net/tun.c:2048\n new_sync_write fs/read_write.c:497 [inline]\n vfs_write+0x76f/0x8d0 fs/read_write.c:590\n ksys_write+0xbf/0x190 fs/read_write.c:643\n __do_sys_write fs/read_write.c:655 [inline]\n __se_sys_write fs/read_write.c:652 [inline]\n __x64_sys_write+0x41/0x50 fs/read_write.c:652\n x64_sys_call+0xe66/0x1990 arch/x86/include/generated/asm/syscalls_64.h:2\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0x4b/0x110 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x4b/0x53\nRIP: 0033:0x7fc44a68bc1f\nCode: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 e9 cf f5 ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 3c d0 f5 ff 48\nRSP: 002b:00007fc449126c90 EFLAGS: 00000293 ORIG_RAX: 0000000000000001\nRAX: ffffffffffffffda RBX: 00000000004bc050 RCX: 00007fc44a68bc1f\nR\n---truncated---", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "6acc9b432e6714d72d7d77ec7c27f6f8358d0c71", "status": "affected", "versionType": "git", "lessThan": "7a67c4e47626e6daccda62888f8b096abb5d3940" }, { "version": "6acc9b432e6714d72d7d77ec7c27f6f8358d0c71", "status": "affected", "versionType": "git", "lessThan": "9f965684c57c3117cfd2f754dd3270383c529fba" }, { "version": "6acc9b432e6714d72d7d77ec7c27f6f8358d0c71", "status": "affected", "versionType": "git", "lessThan": "ddf516e50bf8a7bc9b3bd8a9831f9c7a8131a32a" }, { "version": "6acc9b432e6714d72d7d77ec7c27f6f8358d0c71", "status": "affected", "versionType": "git", "lessThan": "a6db0d3ea6536e7120871e5448b3032570152ec6" }, { "version": "6acc9b432e6714d72d7d77ec7c27f6f8358d0c71", "status": "affected", "versionType": "git", "lessThan": "c5fd77ca13d657c6e99bf04f0917445e6a80231e" }, { "version": "6acc9b432e6714d72d7d77ec7c27f6f8358d0c71", "status": "affected", "versionType": "git", "lessThan": "20ceae10623c3b29fdf7609690849475bcdebdb0" }, { "version": "6acc9b432e6714d72d7d77ec7c27f6f8358d0c71", "status": "affected", "versionType": "git", "lessThan": "5c0b485a8c6116516f33925b9ce5b6104a6eadfd" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "4.20", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "4.20" }, { "version": "5.4.280", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.4.*" }, { "version": "5.10.222", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.163", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.100", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.41", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.9.10", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.9.*" }, { "version": "6.10", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }