CVE-2017-20002 Information

Description

The Debian shadow package before 1:4.5-1 for Shadow incorrectly lists pts/0 and pts/1 as physical terminals in /etc/securetty. This allows local users to login as password-less users even if they are connected by non-physical means such as SSH (hence bypassing PAM’s nullok_secure configuration). This notably affects environments such as virtual machines automatically generated with a default blank root password allowing all local users to escalate privileges.

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Reference

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=914957 https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=877374 https://lists.debian.org/debian-lts-announce/2021/03/msg00020.html

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

7.8