CVE-2017-20002

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 v3 7.8 HIGH
CVSS v2.0 4.6 MEDIUM

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

4.6^/10

CVSS v2.0 : MEDIUM

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

Exploitability : 3.9 / Impact : 6.4

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=877374	Mailing List Vendor Advisory
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=914957	Exploit Mailing List Vendor Advisory
https://lists.debian.org/debian-lts-announce/2021/03/msg00020.html	Mailing List Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:debian:shadow:4.4:::::::*
	cpe:2.3:o:debian:debian_linux:9.0:::::::*

History

No history.

Information

Published : 2021-03-17 06:15

Updated : 2024-02-28 18:08

NVD link : CVE-2017-20002

Mitre link : CVE-2017-20002

CVE.ORG link : CVE-2017-20002

JSON object : View

Products Affected

debian

shadow
debian_linux

CWE

CWE-269

Improper Privilege Management

{"id": "CVE-2017-20002", "metrics": {"cvssMetricV2": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"version": "2.0", "baseScore": 4.6, "accessVector": "LOCAL", "vectorString": "AV:L/AC:L/Au:N/C:P/I:P/A:P", "authentication": "NONE", "integrityImpact": "PARTIAL", "accessComplexity": "LOW", "availabilityImpact": "PARTIAL", "confidentialityImpact": "PARTIAL"}, "acInsufInfo": false, "impactScore": 6.4, "baseSeverity": "MEDIUM", "obtainAllPrivilege": false, "exploitabilityScore": 3.9, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}], "cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 1.8}]}, "published": "2021-03-17T06:15:12.107", "references": [{"url": "https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=877374", "tags": ["Mailing List", "Vendor Advisory"], "source": "cve@mitre.org"}, {"url": "https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=914957", "tags": ["Exploit", "Mailing List", "Vendor Advisory"], "source": "cve@mitre.org"}, {"url": "https://lists.debian.org/debian-lts-announce/2021/03/msg00020.html", "tags": ["Mailing List", "Vendor Advisory"], "source": "cve@mitre.org"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-269"}]}], "descriptions": [{"lang": "en", "value": "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."}, {"lang": "es", "value": "El paquete shadow de Debian versiones anteriores a 4.5-1 para Shadow, enumera incorrectamente pts/0 y pts/1 como terminales f\u00edsicos en /etc/securetty. Esto permite a usuarios locales iniciar sesi\u00f3n como usuarios sin contrase\u00f1a incluso si est\u00e1n conectados por medios no f\u00edsicos como SSH (por lo tanto, omitiendo una configuraci\u00f3n nullok_secure de PAM). Esto afecta notablemente a entornos como las m\u00e1quinas virtuales generadas autom\u00e1ticamente con una contrase\u00f1a root en blanco predeterminada, permitiendo a todos los usuarios locales escalar privilegios"}], "lastModified": "2021-06-07T14:58:56.823", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:debian:shadow:4.4:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "C1317D10-D7BA-4A18-8667-7542A44A4989"}, {"criteria": "cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "DEECE5FC-CACF-4496-A3E7-164736409252"}], "operator": "OR"}]}], "sourceIdentifier": "cve@mitre.org"}