=========================================================================Ubuntu Security Notice USN-5083-1
September 16, 2021

python3.4, python3.5 vulnerabilities
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 16.04 ESM
- Ubuntu 14.04 ESM

Summary:

Several security issues were fixed in Python.

Software Description:
- python3.5: An interactive high-level object-oriented language
- python3.4: An interactive high-level object-oriented language

Details:

It was discovered that Python incorrectly handled certain RFCs.
An attacker could possibly use this issue to cause a denial of service.
This issue only affected Ubuntu 16.04 ESM. (CVE-2021-3733)

It was discovered that Python incorrectly handled certain
server responses. An attacker could possibly use this issue to
cause a denial of service. (CVE-2021-3737)

Update instructions:

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

Ubuntu 16.04 ESM:
  python3.5                       3.5.2-2ubuntu0~16.04.13+esm1
  python3.5-minimal               3.5.2-2ubuntu0~16.04.13+esm1

Ubuntu 14.04 ESM:
  python3.4                       3.4.3-1ubuntu1~14.04.7+esm11
  python3.4-minimal               3.4.3-1ubuntu1~14.04.7+esm11

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

References:
  https://ubuntu.com/security/notices/USN-5083-1
  CVE-2021-3733, CVE-2021-3737