Ubuntu Security Notice 5821-4 - USN-5821-3 fixed a vulnerability in pip. The update introduced a minor regression in Ubuntu 14.04 ESM, Ubuntu 16.04 ESM and Ubuntu 18.04 LTS. This update fixes the problem. Sebastian Chnelik discovered that wheel incorrectly handled certain file names when validated against a regex expression. An attacker could possibly use this issue to cause a denial of service. Continue reading...