Ubuntu 20.04 LTS USN-4747-1 Critical: Screen Denial of Service

ubuntu

February 24, 2021

GNU Screen could be made to crash or run programs if it processed specially crafted character sequences.

Summary

GNU Screen could be made to crash or run programs if it processed specially

crafted character sequences.

Software Description:

- screen: terminal multiplexer with VT100/ANSI terminal emulation

Details:

Felix Weinmann discovered that GNU Screen incorrectly handled certain

character sequences. A remote attacker could use this issue to cause GNU

Screen to crash, resulting in a denial of service, or possibly execute

arbitrary code.

Topics Covered

security advisory denial of service critical remote code execution Ubuntu update instructions screen ubuntu program crash

Update Instructions

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

Ubuntu 20.10:
  screen                          4.8.0-2ubuntu0.1

Ubuntu 20.04 LTS:
  screen                          4.8.0-1ubuntu0.1

Ubuntu 18.04 LTS:
  screen                          4.6.2-1ubuntu1.1

Ubuntu 16.04 LTS:
  screen                          4.3.1-2ubuntu0.1

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