{"id":"AZL-92868","summary":"CVE-2026-64189 affecting package kernel for versions less than 6.6.145.2-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ipset: fix race between dump and ip_set_list resize\n\nThe release path of ip_set_dump_do() and ip_set_dump_done() read\ninst-\u003eip_set_list via ip_set_ref_netlink(), a plain rcu_dereference_raw()\nof the array pointer. These run from netlink_recvmsg() without the nfnl\nmutex and without an RCU read-side critical section.\n\nA concurrent ip_set_create() can grow the array: it publishes the new\narray, calls synchronize_net() and then kvfree()s the old one. Since the\ndump paths read the array outside any RCU reader, synchronize_net() does\nnot wait for them and the old array can be freed while they still index\ninto it, causing a use-after-free.\n\nThe dumped set itself stays pinned via set-\u003eref_netlink, so only the\narray load needs protecting. Take rcu_read_lock() around it, matching\nip_set_get_byname() and __ip_set_put_byindex().\n\n  BUG: KASAN: slab-use-after-free in ip_set_dump_do (net/netfilter/ipset/ip_set_core.c:1697)\n  Read of size 8 at addr ffff88800b5c4018 by task exploit/150\n  Call Trace:\n   ...\n   kasan_report (mm/kasan/report.c:595)\n   ip_set_dump_do (net/netfilter/ipset/ip_set_core.c:1697)\n   netlink_dump (net/netlink/af_netlink.c:2325)\n   netlink_recvmsg (net/netlink/af_netlink.c:1976)\n   sock_recvmsg (net/socket.c:1159)\n   __sys_recvfrom (net/socket.c:2315)\n   ...\n  Oops: general protection fault, probably for non-canonical address ... KASAN NOPTI\n  KASAN: maybe wild-memory-access in range [0x02d6...d0-0x02d6...d7]\n  RIP: 0010:ip_set_dump_do (net/netfilter/ipset/ip_set_core.c:1698)\n  Kernel panic - not syncing: Fatal exception","modified":"2026-08-28T17:47:18.635350185Z","published":"2026-07-20T17:18:21Z","upstream":["CVE-2026-64189"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64189"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.145.2-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-92868.json"}}],"schema_version":"1.9.0"}