A Python-RSA security update has been released for Ubuntu Linux 14.04 ESM.

USN-4478-1: Python-RSA vulnerability

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Ubuntu Security Notice USN-4478-1
August 31, 2020

python-rsa vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 14.04 ESM

Summary:

Python-RSA could be made to expose sensitive information over the
network.

Software Description:
- python-rsa: Pure-Python RSA implementation (Python 2)

Details:

It was discovered that Python-RSA incorrectly handled certain ciphertexts.
An attacker could possibly use this issue to obtain sensitive information.

Update instructions:

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

Ubuntu 14.04 ESM:
python-rsa 3.1.2-1ubuntu0.1+esm1
python3-rsa 3.1.2-1ubuntu0.1+esm1

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

References:
  https://usn.ubuntu.com/4478-1
CVE-2020-13757