==========================================================================
Ubuntu Security Notice USN-5155-1
November 23, 2021

bluez vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 21.10
- Ubuntu 21.04
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS

Summary:

Several security issues were fixed in BlueZ.

Software Description:
- bluez: Bluetooth tools and daemons

Details:

It was discovered that BlueZ incorrectly handled the Discoverable status
when a device is powered down. This could result in devices being powered
up discoverable, contrary to expectations. This issue only affected Ubuntu
20.04 LTS, Ubuntu 21.04, and Ubuntu 21.10. (CVE-2021-3658)

It was discovered that BlueZ incorrectly handled certain memory operations.
A remote attacker could possibly use this issue to cause BlueZ to consume
resources, leading to a denial of service. (CVE-2021-41229)

It was discovered that the BlueZ gatt server incorrectly handled
disconnects. A remote attacker could possibly use this issue to cause
BlueZ to crash, leading to a denial of service. (CVE-2021-43400)

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 21.10:
  bluez                           5.60-0ubuntu2.1
  libbluetooth3                   5.60-0ubuntu2.1

Ubuntu 21.04:
  bluez                           5.56-0ubuntu4.3
  libbluetooth3                   5.56-0ubuntu4.3

Ubuntu 20.04 LTS:
  bluez                           5.53-0ubuntu3.4
  libbluetooth3                   5.53-0ubuntu3.4

Ubuntu 18.04 LTS:
  bluez                           5.48-0ubuntu3.6
  libbluetooth3                   5.48-0ubuntu3.6

In general, a standard system update will make all the necessary changes.

References:
  https://ubuntu.com/security/notices/USN-5155-1
  CVE-2021-3658, CVE-2021-41229, CVE-2021-43400

Package Information:
  https://launchpad.net/ubuntu/+source/bluez/5.60-0ubuntu2.1
  https://launchpad.net/ubuntu/+source/bluez/5.56-0ubuntu4.3
  https://launchpad.net/ubuntu/+source/bluez/5.53-0ubuntu3.4
  https://launchpad.net/ubuntu/+source/bluez/5.48-0ubuntu3.6