{"id":"AZL-102066","summary":"CVE-2026-90170 affecting package kernel 6.6.150.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: validate ipc response length before dereferencing its fields\n\nipc_validate_msg() computes the expected message size by reading length\nfields out of the response buffer supplied by the userspace ksmbd daemon\n(payload_sz, session_key_len, ngroups, ...).  Those fields are read before\nthe buffer is verified to be large enough to contain the struct they belong\nto, so a short response makes the read land past the end of the allocation.\n\nhandle_response() sizes entry-\u003eresponse purely from the netlink attribute\nlength (nla_len()) and only guards the leading handle read, so the daemon\ncan install a response as small as the kmalloc-8 object seen below.  When\nipc_msg_send_request() then calls ipc_validate_msg() for a\nKSMBD_EVENT_RPC_REQUEST, the cast to struct ksmbd_rpc_command reads\nresp-\u003epayload_sz at offset 8 of an 8-byte allocation:\n\n[ 3697.841381] ==================================================================\n[ 3697.844099] BUG: KASAN: slab-out-of-bounds in ipc_msg_send_request+0x763/0x800\n[ 3697.846604] Read of size 4 at addr ffff888105f95910 by task kworker/4:3/20682\n[ 3697.849061]\n[ 3697.849801] CPU: 4 UID: 0 PID: 20682 Comm: kworker/4:3 Not tainted 7.2.0-rc3-next-20260717-virtme #117 PREEMPT(lazy)\n[ 3697.850077] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04/01/2014\n[ 3697.850303] Workqueue: ksmbd-io handle_ksmbd_work\n[ 3697.850592] Call Trace:\n[ 3697.850794]  \u003cTASK\u003e\n[ 3697.850952]  __dump_stack+0x21/0x60\n[ 3697.851239]  dump_stack_lvl+0xc2/0x100\n[ 3697.851528]  print_address_description+0x77/0x200\n[ 3697.851816]  ? ipc_msg_send_request+0x763/0x800\n[ 3697.852024]  print_report+0x58/0x70\n[ 3697.852316]  kasan_report+0x117/0x150\n[ 3697.852585]  ? down_write+0x146/0x1f0\n[ 3697.852809]  ? ipc_msg_send_request+0x763/0x800\n[ 3697.853082]  ipc_msg_send_request+0x763/0x800\n[ 3697.853385]  ? __pfx_ipc_msg_send_request+0x10/0x10\n[ 3697.853604]  ? kasan_unpoison+0x48/0x70\n[ 3697.853936]  ? __pfx___up_read+0x10/0x10\n[ 3697.854221]  ksmbd_rpc_ioctl+0x380/0x520\n[ 3697.854542]  ? __pfx_ksmbd_rpc_ioctl+0x10/0x10\n[ 3697.854757]  ? kasan_unpoison+0x48/0x70\n[ 3697.854962]  ? copy_from_kernel_nofault+0x32c/0x4e0\n[ 3697.855166]  ? kasan_unpoison+0x48/0x70\n[ 3697.855416]  fsctl_pipe_transceive+0x139/0x7a0\n[ 3697.855705]  ? __pfx_copy_from_kernel_nofault+0x10/0x10\n[ 3697.855937]  ? __pfx_fsctl_pipe_transceive+0x10/0x10\n[ 3697.856388]  ? __sanitizer_cov_trace_switch+0x7b/0x140\n[ 3697.856620]  smb2_ioctl+0x1141/0x3420\n[ 3697.856994]  ? __pfx_smb2_ioctl+0x10/0x10\n[ 3697.857182]  ? get_smb2_cmd_val+0xe3/0x1c0\n[ 3697.857655]  handle_ksmbd_work+0x9ad/0x15e0\n[ 3697.858034]  ? __pfx_handle_ksmbd_work+0x10/0x10\n[ 3697.858251]  ? lock_release+0xf7/0x360\n[ 3697.858466]  ? process_scheduled_works+0x954/0x1600\n[ 3697.858698]  ? process_scheduled_works+0x954/0x1600\n[ 3697.858905]  process_scheduled_works+0xc22/0x1600\n[ 3697.859368]  ? __pfx_process_scheduled_works+0x10/0x10\n[ 3697.859637]  ? __pfx_assign_work+0x10/0x10\n[ 3697.859896]  ? lock_is_held_type+0x7b/0x110\n[ 3697.860146]  worker_thread+0x975/0xee0\n[ 3697.860524]  ? __pfx_do_raw_spin_lock+0x10/0x10\n[ 3697.860830]  ? __kthread_parkme+0x21e/0x260\n[ 3697.861105]  kthread+0x3a6/0x490\n[ 3697.861423]  ? __pfx_worker_thread+0x10/0x10\n[ 3697.861643]  ? __pfx_kthread+0x10/0x10\n[ 3697.861878]  ret_from_fork+0x55a/0xa20\n[ 3697.862194]  ? __pfx_ret_from_fork+0x10/0x10\n[ 3697.862480]  ? __pfx_kthread+0x10/0x10\n[ 3697.862714]  ret_from_fork_asm+0x1a/0x30\n[ 3697.862965]  \u003c/TASK\u003e\n[ 3697.863039]\n[ 3697.938882] Allocated by task 20761:\n[ 3697.940257]  kasan_save_track+0x3e/0x80\n[ 3697.941782]  __kasan_kmalloc+0x72/0x90\n[ 3697.943228]  __kvmalloc_node_noprof+0x3e9/0x6a0\n[ 3697.944948]  handle_generic_event+0x59b/0x750\n[ 3697.946592]  genl_family_rcv_msg_doit+0x3d6/0x560\n[ 3697.946977]  genl_rcv_msg+0x67c/0x900\n[ 3697.947224]  netlink_rcv_skb+0x286/0x580\n[ 3697.947488]  genl_rcv+0x2d/0x80\n[ 3\n---truncated---","modified":"2026-09-20T05:33:47Z","published":"2026-09-17T17:17:10Z","upstream":["CVE-2026-90170"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90170"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.150.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-102066.json"}}],"schema_version":"1.9.0"}