CVE-2017-20002 Auth bypass in n/a

What is CVE-2017-20002?

CVE-2017-20002 is a high-severity authentication bypass vulnerability in Debian Debian Linux, published on 17 Mar 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official 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.

Weakness: CWE-269

Which versions are affected by CVE-2017-20002?

It affects 2 products.

Products include Debian Debian Linux, Debian Shadow.

How do I fix CVE-2017-20002?

Upgrade to a fixed version.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2017-20002 being exploited?

There is no known exploitation of CVE-2017-20002 in the wild and no public exploit code.

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All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2017-20002, GHSA-2m59-rw4g-9g7x.