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CVE-2016-5117
OpenNTPD before 6.0p1 does not validate the CN for HTTPS constraint requests, which allows remote attackers to bypass the…
Medium5.9EPSS 0.70%
- Published
- Updated
- Reserved
- Assigned by
- mitre
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.0 | Medium5.9 | CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N |
- EPSS (exploitation in 30 days)
- 0.70% · top 47% of all CVEs (2 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.9.
Weakness
Affected products
n/a
- affected n/a
References (4)
- http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.sbin/ntpd/constraint.c.diff?r1=1.27&r2=1.28 (opens in a new tab)x_refsource_CONFIRMx_transferred
- [oss-security] 20160523 CVE request: OpenNTPD not verifying CN during HTTPS constraints request (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- [oss-security] 20160529 Re: CVE request: OpenNTPD not verifying CN during HTTPS constraints request (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- http://www.openntpd.org/txt/release-6.0p1.txt (opens in a new tab)x_refsource_CONFIRMx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Record last updated .