{"id":"CVE-2016-5117","aliases":["DEBIAN-CVE-2016-5117","EUVD-2016-6068","GHSA-4m25-49gx-cpq6"],"status":"published","title":"OpenNTPD before 6.0p1 does not validate the CN for HTTPS constraint requests, which allows remote...","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.","severity":{"version":"3.0","score":5.9,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-07","score":0.00702,"percentile":0.53489,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-254"],"published":"2017-01-31T19:00:00Z","modified":"2026-09-22T07:02:21Z","fixes":[{"ecosystem":"Debian:12","package":"openntpd","fixed_in":["1:6.0p1-1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"openntpd","fixed_in":["1:6.0p1-1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"openntpd","fixed_in":["1:6.0p1-1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"openntpd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:6.0p1-1"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"openntpd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:6.0p1-1"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"openntpd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:6.0p1-1"}]}]}],"products":[{"vendor":"openntpd","product":"openntpd"}],"references":[{"url":"http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.sbin/ntpd/constraint.c.diff?r1=1.27\u0026r2=1.28","tags":["x_refsource_CONFIRM","x_transferred","Patch","fix"]},{"url":"http://www.openwall.com/lists/oss-security/2016/05/23/2","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List","Third Party Advisory","advisory"]},{"url":"http://www.openwall.com/lists/oss-security/2016/05/29/6","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List","Third Party Advisory","advisory"]},{"url":"http://www.openntpd.org/txt/release-6.0p1.txt","tags":["x_refsource_CONFIRM","x_transferred","Vendor Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2016-5117"},{"url":"https://github.com/advisories/GHSA-4m25-49gx-cpq6"},{"url":"https://security-tracker.debian.org/tracker/CVE-2016-5117","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2016-5117","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.","status":"published","published":"2017-01-31T19:00:00Z","modified":"2024-08-06T00:53:47.349Z","updated_at":"2026-11-02T14:33:31.117878Z"}],"euvd":[{"id":"EUVD-2016-6068","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.","status":"published","published":"2017-01-31T19:00:00Z","modified":"2024-08-06T00:53:47Z","updated_at":"2026-11-03T02:22:43.959327Z"}],"ghsa":[{"id":"GHSA-4m25-49gx-cpq6","title":"OpenNTPD before 6.0p1 does not validate the CN for HTTPS constraint requests, which allows remote...","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.","status":"published","published":"2022-05-17T02:57:52Z","modified":"2023-01-27T05:06:57Z","cvss":[{"version":"3.0","score":5.9,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"medium"}],"updated_at":"2026-11-02T14:43:01.321842Z"}],"nvd":[{"id":"CVE-2016-5117","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.","status":"published","published":"2017-01-31T19:59:00.23Z","modified":"2026-06-17T00:48:47.21Z","cvss":[{"version":"3.0","score":5.9,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":4.3,"vector":"AV:N/AC:M/Au:N/C:N/I:P/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-254"],"updated_at":"2026-11-02T14:03:35.029632Z"}],"osv":[{"id":"CVE-2016-5117","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.","status":"published","published":"2017-01-31T19:59:00.23Z","modified":"2026-03-14T14:16:00.133303Z","cvss":[{"version":"3.0","score":5.9,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:02.454775Z"},{"id":"DEBIAN-CVE-2016-5117","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.","status":"published","published":"2017-01-31T19:59:00.23Z","modified":"2026-09-22T07:02:21.672849649Z","cvss":[{"version":"3.0","score":5.9,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"medium"}],"updated_at":"2026-11-02T15:45:27.627285Z"}]}}