CVE-2017-20002
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).
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.40%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.40% probability · 35th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-269
- Affected
- debian/shadow · debian/debian linux
- Source
- cve@mitre.org
EPSS 0.4% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=877374Mailing List, Vendor Advisory
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=914957Exploit, Mailing List, Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2021/03/msg00020.htmlMailing List, Vendor Advisory
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=877374Mailing List, Vendor Advisory
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=914957Exploit, Mailing List, Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2021/03/msg00020.htmlMailing List, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.