CVE-2016-7431
NTP before 4.2.8p9 allows remote attackers to bypass the origin timestamp protection mechanism via an origin timestamp of zero.
Does this matter?
Lower severity and a low EPSS score (8.88%). Track it; it rarely justifies an emergency change on its own.
Description
NTP before 4.2.8p9 allows remote attackers to bypass the origin timestamp protection mechanism via an origin timestamp of zero. NOTE: this vulnerability exists because of a CVE-2015-8138 regression.
- CVSS 3.0
- 5.3 MEDIUMCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- EPSS
- 8.88% probability · 95th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-20
- Affected
- ntp/ntp
- Source
- cve@mitre.org
EPSS moved from 10.4% on 21 September 2026 to 8.9% on 27 October 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.
References
- http://lists.opensuse.org/opensuse-updates/2016-12/msg00153.html
- http://nwtime.org/ntp428p9_release/Release Notes, Vendor Advisory
- http://packetstormsecurity.com/files/140240/FreeBSD-Security-Advisory-FreeBSD-SA-16.39.ntp.html
- http://support.ntp.org/bin/view/Main/NtpBug3102Issue Tracking, Mitigation, Vendor Advisory
- http://support.ntp.org/bin/view/Main/SecurityNotice#Recent_VulnerabilitiesVendor Advisory
- http://www.huawei.com/en/psirt/security-advisories/huawei-sa-20171129-01-ntpd-en
- http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html
- http://www.securityfocus.com/archive/1/539955/100/0/threaded
- http://www.securityfocus.com/archive/1/540254/100/0/threaded
- http://www.securityfocus.com/archive/1/archive/1/539955/100/0/threaded
- http://www.securityfocus.com/archive/1/archive/1/540254/100/0/threaded
- http://www.securityfocus.com/bid/94454
- http://www.securitytracker.com/id/1037354
- http://www.ubuntu.com/usn/USN-3349-1
- https://bto.bluecoat.com/security-advisory/sa139
- https://cert-portal.siemens.com/productcert/pdf/ssa-211752.pdf
- https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03706en_us
- https://security.FreeBSD.org/advisories/FreeBSD-SA-16:39.ntp.asc
- https://support.hpe.com/hpsc/doc/public/display?docLocale=en&docId=emr_na-hpesbhf03883en_us
- https://support.hpe.com/hpsc/doc/public/display?docLocale=en&docId=emr_na-hpesbhf03899en_us
- https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03883en_us
- https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03899en_us
- https://us-cert.cisa.gov/ics/advisories/icsa-21-159-11
- https://www.broadcom.com/support/fibre-channel-networking/security-advisories/brocade-security-advisory-2017-223/
- https://www.kb.cert.org/vuls/id/633847Third Party Advisory, US Government Resource
- http://lists.opensuse.org/opensuse-updates/2016-12/msg00153.html
- http://nwtime.org/ntp428p9_release/Release Notes, Vendor Advisory
- http://packetstormsecurity.com/files/140240/FreeBSD-Security-Advisory-FreeBSD-SA-16.39.ntp.html
- http://support.ntp.org/bin/view/Main/NtpBug3102Issue Tracking, Mitigation, Vendor Advisory
- http://support.ntp.org/bin/view/Main/SecurityNotice#Recent_VulnerabilitiesVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.