A BlueZ security update has been released for Ubuntu Linux 16.04 ESM.

USN-4989-2: BlueZ vulnerabilities

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Ubuntu Security Notice USN-4989-2
June 16, 2021

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

- Ubuntu 16.04 ESM

Summary:

Several security issues were fixed in BlueZ.

Software Description:
- bluez: Bluetooth tools and daemons

Details:

USN-4989-1 fixed several vulnerabilities in BlueZ. This update provides
the corresponding update for Ubuntu 16.04 ESM.

Original advisory details:

It was discovered that BlueZ incorrectly checked certain permissions when
pairing. A local attacker could possibly use this issue to impersonate
devices. (CVE-2020-26558)

Jay LV discovered that BlueZ incorrectly handled redundant disconnect MGMT
events. A local attacker could use this issue to cause BlueZ to crash,
resulting in a denial of service, or possibly execute arbitrary code. This
issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2020-27153)

Update instructions:

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

Ubuntu 16.04 ESM:
bluez 5.37-0ubuntu5.3+esm1
libbluetooth3 5.37-0ubuntu5.3+esm1

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

References:
  https://ubuntu.com/security/notices/USN-4989-2
  https://ubuntu.com/security/notices/USN-4989-1
CVE-2020-26558, CVE-2020-27153