A use-after-free in function hci_sock_bound_ioctl() of the Linux kernel HCI subsystem was found in the way user calls ioct HCIUNBLOCKADDR or other way triggers race condition of the call hci_unregister_dev() together with one of the calls hci_sock_blacklist_add() hci_sock_blacklist_del() hci_get_conn_info() hci_get_auth_info(). A privileged local user could use this flaw to crash the system or escalate their privileges on the system. This flaw affects the Linux kernel versions prior to 5.13-rc5.

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UBUNTU-CVE-2021-3573

A use-after-free in function hcisockboundioctl of the Linux kernel HCI subsystem was found in the way user calls ioct HCIUNBLOCKADDR or other way triggers race condition of the call hciunregisterdev together with one of the calls hcisockblacklistadd, hcisockblacklistdel, hcigetconninfo,...