{"id":"AZL-67737","summary":"CVE-2024-35839 affecting package kernel 5.15.200.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: bridge: replace physindev with physinif in nf_bridge_info\n\nAn skb can be added to a neigh-\u003earp_queue while waiting for an arp\nreply. Where original skb's skb-\u003edev can be different to neigh's\nneigh-\u003edev. For instance in case of bridging dnated skb from one veth to\nanother, the skb would be added to a neigh-\u003earp_queue of the bridge.\n\nAs skb-\u003edev can be reset back to nf_bridge-\u003ephysindev and used, and as\nthere is no explicit mechanism that prevents this physindev from been\nfreed under us (for instance neigh_flush_dev doesn't cleanup skbs from\ndifferent device's neigh queue) we can crash on e.g. this stack:\n\narp_process\n  neigh_update\n    skb = __skb_dequeue(&neigh-\u003earp_queue)\n      neigh_resolve_output(..., skb)\n        ...\n          br_nf_dev_xmit\n            br_nf_pre_routing_finish_bridge_slow\n              skb-\u003edev = nf_bridge-\u003ephysindev\n              br_handle_frame_finish\n\nLet's use plain ifindex instead of net_device link. To peek into the\noriginal net_device we will use dev_get_by_index_rcu(). Thus either we\nget device and are safe to use it or we don't get it and drop skb.","modified":"2026-04-01T05:21:16.644514Z","published":"2024-05-17T15:15:21Z","upstream":["CVE-2024-35839"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-35839"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:2","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"5.15.200.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-67737.json"}}],"schema_version":"1.7.5"}