CVE-2016-5117 - Vulnerability Details - OpenCVE

Description

OpenNTPD before 6.0p1 does not validate the CN for HTTPS constraint requests, which allows remote attackers to bypass the man-in-the-middle mitigations via a crafted timestamp constraint with a valid certificate.

Published: 2017-01-31

Score: 5.9 Medium

EPSS: < 1% Very Low

KEV: No

Impact:

Action:

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

n/a

n/a

affected

Version	Status	Constraints
`n/a`	affected	—

Configuration 1 [-]

cpe:2.3:a:openntpd:openntpd:*:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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Advisories

Source	ID	Title
EUVD	EUVD-2016-6068	OpenNTPD before 6.0p1 does not validate the CN for HTTPS constraint requests, which allows remote attackers to bypass the man-in-the-middle mitigations via a crafted timestamp constraint with a valid certificate.

No CVSS v4.0

No CVSS v3.1

Attack Vector Network

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact High

Availability Impact None

User Interaction None

Access Vector Network

Access Complexity Medium

Authentication None

Confidentiality Impact None

Integrity Impact Partial

Availability Impact None

This CVE is not in the KEV list.

The EPSS score is 0.0027.

Key SSVC decision points have not yet been added.

References

Link	Providers
http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.sbin/ntpd/constraint.c.diff?r1=1.27&r2=1.28
http://www.openntpd.org/txt/release-6.0p1.txt
http://www.openwall.com/lists/oss-security/2016/05/23/2
http://www.openwall.com/lists/oss-security/2016/05/29/6

History

No history.

Subscriptions

Openntpd Openntpd

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2017-01-31T19:00:00.000Z

Updated: 2024-08-06T00:53:47.349Z

Reserved: 2016-05-29T00:00:00.000Z

Link: CVE-2016-5117

Vulnrichment

No data.

NVD

Status : Modified

Published: 2017-01-31T19:59:00.230

Modified: 2026-05-13T00:24:29.033

Link: CVE-2016-5117

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-254

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