{"id":"AZL-42031","summary":"CVE-2024-27018 affecting package hyperv-daemons for versions less than 5.15.158.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: br_netfilter: skip conntrack input hook for promisc packets\n\nFor historical reasons, when bridge device is in promisc mode, packets\nthat are directed to the taps follow bridge input hook path. This patch\nadds a workaround to reset conntrack for these packets.\n\nJianbo Liu reports warning splats in their test infrastructure where\ncloned packets reach the br_netfilter input hook to confirm the\nconntrack object.\n\nScratch one bit from BR_INPUT_SKB_CB to annotate that this packet has\nreached the input hook because it is passed up to the bridge device to\nreach the taps.\n\n[   57.571874] WARNING: CPU: 1 PID: 0 at net/bridge/br_netfilter_hooks.c:616 br_nf_local_in+0x157/0x180 [br_netfilter]\n[   57.572749] Modules linked in: xt_MASQUERADE nf_conntrack_netlink nfnetlink iptable_nat xt_addrtype xt_conntrack nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcgss oid_registry overlay rpcrdma rdma_ucm ib_iser libiscsi scsi_transport_isc si ib_umad rdma_cm ib_ipoib iw_cm ib_cm mlx5_ib ib_uverbs ib_core mlx5ctl mlx5_core\n[   57.575158] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.8.0+ #19\n[   57.575700] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\n[   57.576662] RIP: 0010:br_nf_local_in+0x157/0x180 [br_netfilter]\n[   57.577195] Code: fe ff ff 41 bd 04 00 00 00 be 04 00 00 00 e9 4a ff ff ff be 04 00 00 00 48 89 ef e8 f3 a9 3c e1 66 83 ad b4 00 00 00 04 eb 91 \u003c0f\u003e 0b e9 f1 fe ff ff 0f 0b e9 df fe ff ff 48 89 df e8 b3 53 47 e1\n[   57.578722] RSP: 0018:ffff88885f845a08 EFLAGS: 00010202\n[   57.579207] RAX: 0000000000000002 RBX: ffff88812dfe8000 RCX: 0000000000000000\n[   57.579830] RDX: ffff88885f845a60 RSI: ffff8881022dc300 RDI: 0000000000000000\n[   57.580454] RBP: ffff88885f845a60 R08: 0000000000000001 R09: 0000000000000003\n[   57.581076] R10: 00000000ffff1300 R11: 0000000000000002 R12: 0000000000000000\n[   57.581695] R13: ffff8881047ffe00 R14: ffff888108dbee00 R15: ffff88814519b800\n[   57.582313] FS:  0000000000000000(0000) GS:ffff88885f840000(0000) knlGS:0000000000000000\n[   57.583040] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[   57.583564] CR2: 000000c4206aa000 CR3: 0000000103847001 CR4: 0000000000370eb0\n[   57.584194] DR0: 0000000000000000 DR1: 0000000000000000 DR2:\n0000000000000000\n[   57.584820] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:\n0000000000000400\n[   57.585440] Call Trace:\n[   57.585721]  \u003cIRQ\u003e\n[   57.585976]  ? __warn+0x7d/0x130\n[   57.586323]  ? br_nf_local_in+0x157/0x180 [br_netfilter]\n[   57.586811]  ? report_bug+0xf1/0x1c0\n[   57.587177]  ? handle_bug+0x3f/0x70\n[   57.587539]  ? exc_invalid_op+0x13/0x60\n[   57.587929]  ? asm_exc_invalid_op+0x16/0x20\n[   57.588336]  ? br_nf_local_in+0x157/0x180 [br_netfilter]\n[   57.588825]  nf_hook_slow+0x3d/0xd0\n[   57.589188]  ? br_handle_vlan+0x4b/0x110\n[   57.589579]  br_pass_frame_up+0xfc/0x150\n[   57.589970]  ? br_port_flags_change+0x40/0x40\n[   57.590396]  br_handle_frame_finish+0x346/0x5e0\n[   57.590837]  ? ipt_do_table+0x32e/0x430\n[   57.591221]  ? br_handle_local_finish+0x20/0x20\n[   57.591656]  br_nf_hook_thresh+0x4b/0xf0 [br_netfilter]\n[   57.592286]  ? br_handle_local_finish+0x20/0x20\n[   57.592802]  br_nf_pre_routing_finish+0x178/0x480 [br_netfilter]\n[   57.593348]  ? br_handle_local_finish+0x20/0x20\n[   57.593782]  ? nf_nat_ipv4_pre_routing+0x25/0x60 [nf_nat]\n[   57.594279]  br_nf_pre_routing+0x24c/0x550 [br_netfilter]\n[   57.594780]  ? br_nf_hook_thresh+0xf0/0xf0 [br_netfilter]\n[   57.595280]  br_handle_frame+0x1f3/0x3d0\n[   57.595676]  ? br_handle_local_finish+0x20/0x20\n[   57.596118]  ? br_handle_frame_finish+0x5e0/0x5e0\n[   57.596566]  __netif_receive_skb_core+0x25b/0xfc0\n[   57.597017]  ? __napi_build_skb+0x37/0x40\n[   57.597418]  __netif_receive_skb_list_core+0xfb/0x220","modified":"2026-04-01T05:14:26.370673Z","published":"2024-05-01T06:15:20Z","upstream":["CVE-2024-27018"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-27018"}],"affected":[{"package":{"name":"hyperv-daemons","ecosystem":"Azure Linux:2","purl":"pkg:rpm/azure-linux/hyperv-daemons"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.15.158.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-42031.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}