Affected: kernel

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.

Affected: Ubuntu:20.04:LTS: linux-oem-5.10

It was discovered that the virtual file system implementation in the Linux kernel contained an unsigned to signed integer conversion error. A local attacker could use this to cause a denial of service (system crash) or execute arbitrary code. (CVE-2021-33909)

Michael Brown discovered that the Xen netback driver in the Linux kernel did not properly handle malformed packets from a network PV frontend, leading to a use-after-free vulnerability. An attacker in a guest VM could use this to cause a denial of service or possibly execute arbitrary code. (CVE-2021-28691)

It was discovered that the bluetooth subsystem in the Linux kernel did not properly handle HCI device initialization failure, leading to a double-free vulnerability. An attacker could use this to cause a denial of service or possibly execute arbitrary code. (CVE-2021-3564)

It was discovered that the bluetooth subsystem in the Linux kernel did not properly handle HCI device detach events, leading to a use-after-free vulnerability. An attacker could use this to cause a denial of service or possibly execute arbitrary code. (CVE-2021-3573)

It was discovered that the NFC implementation in the Linux kernel did not properly handle failed connect events leading to a NULL pointer dereference. A local attacker could use this to cause a denial of service. (CVE-2021-3587)