CVE-2016-5117 json
OpenNTPD before 6.0p1 does not validate the CN for HTTPS constraint requests, which allows remote attackers to bypass the man-in-the-middle…
published 2017-01-31 9 y ago modified 2026-06-17 4 mo ago also EUVD-2016-6068
- cvss
- 5.9
- version 3.0, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 53%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- openntpd Debian 14, Debian 13, Debian 12 1:6.0p1-1
debian advisories DEBIAN-CVE-2016-5117
Exploit prediction
0.70% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.0 | 5.9 | CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
Classification
- Weakness
-
- CWE-254 7PK - Security Features
References
-
cvsweb.openbsd.org
/cgi-bin/cvsweb/src/usr.sbin/ntpd/constraint.c.diff?r1=1.27&r2=1.28
patch
-
openntpd.org
/txt/release-6.0p1.txt
vendor-advisory
-
openwall.com
/lists/oss-security/2016/05/23/2
mailing-list, third-party-advisory
-
openwall.com
/lists/oss-security/2016/05/29/6
mailing-list, third-party-advisory
Sources
- CVE List CVE-2016-5117
- NVD CVE-2016-5117
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