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

critical Nessus Plugin ID 150023
New! Plugin Severity Now Using CVSS v3

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Synopsis

The remote Gentoo host is missing one or more security-related patches.

Description

The remote host is affected by the vulnerability described in GLSA-202105-11 (GNU Screen: User-assisted execution of arbitrary code)

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.

Solution

All GNU screen users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose '>=app-misc/screen-4.8.0-r2'

See Also

https://security.gentoo.org/glsa/202105-11

Plugin Details

Severity: Critical

ID: 150023

File Name: gentoo_GLSA-202105-11.nasl

Version: 1.2

Type: local

Published: 5/27/2021

Updated: 6/1/2021

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.5

Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:gentoo:linux:screen, cpe:/o:gentoo:linux

Required KB Items: Host/local_checks_enabled, Host/Gentoo/release, Host/Gentoo/qpkg-list

Exploit Ease: No known exploits are available

Patch Publication Date: 5/26/2021

Vulnerability Publication Date: 2/9/2021

Reference Information

CVE: CVE-2021-26937

GLSA: 202105-11