GNU Screen: User-assisted execution of arbitrary code — GLSA 202105-11

A vulnerability in GNU screen may allow a remote attacker to execute arbitrary code.

Affected packages

Background

GNU Screen is a full-screen window manager that multiplexes a physical terminal between several processes, typically interactive shells.

Description

It was discovered that GNU screen did not properly handle certain UTF-8 character sequences.

Impact

A remote attacker could entice a user to run a program where attacker controls the output inside a GNU screen session, possibly resulting in execution of arbitrary code with the privileges of the process or a Denial of Service condition.

Workaround

This vulnerability can be mitigated by disabling UTF-8 processing in .screenrc.

Resolution

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=app-misc/screen-4.8.0-r2"
 

References

• CVE-2021-26937

Release date
May 26, 2021

Latest revision
May 26, 2021: 1

Severity
normal

Exploitable
local, remote

Bugzilla entries

• 769770