CVE-2016-4956
ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (interleaved-mode transition and time change) via a spoofed broadcast packet.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 16.4%, higher than 97% of all known CVEs. Patch or mitigate before the next change window.
Description
ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (interleaved-mode transition and time change) via a spoofed broadcast packet. NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-1548.
- CVSS 3.1
- 5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- EPSS
- 16.35% probability · 97th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Affected
- ntp/ntp · oracle/solaris · suse/manager proxy · suse/openstack cloud · novell/suse manager · opensuse/leap · opensuse/opensuse · suse/linux enterprise desktop · suse/linux enterprise server · siemens/simatic net cp 443-1 opc ua firmware
- Source
- cve@mitre.org
EPSS 16.4% since 4 November 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://bugs.ntp.org/3042Issue Tracking, Vendor Advisory
- http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00018.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00020.html
- http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00023.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00024.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00028.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00040.htmlMailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2016-07/msg00026.html
- http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00042.html
- http://packetstormsecurity.com/files/137321/Slackware-Security-Advisory-ntp-Updates.html
- http://support.ntp.org/bin/view/Main/NtpBug3042Vendor Advisory
- http://support.ntp.org/bin/view/Main/SecurityNoticeRelease Notes, Vendor Advisory
- http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160603-ntpd
- http://www.kb.cert.org/vuls/id/321640Third Party Advisory, US Government Resource
- http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.htmlThird Party Advisory
- http://www.securityfocus.com/archive/1/538599/100/0/threaded
- http://www.securityfocus.com/archive/1/538600/100/0/threaded
- http://www.securityfocus.com/archive/1/540683/100/0/threaded
- http://www.securityfocus.com/archive/1/archive/1/538599/100/0/threaded
- http://www.securityfocus.com/archive/1/archive/1/538600/100/0/threaded
- http://www.securityfocus.com/archive/1/archive/1/540683/100/0/threaded
- http://www.securityfocus.com/bid/91009Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1036037Third Party Advisory, VDB Entry
- http://www.ubuntu.com/usn/USN-3096-1
- https://cert-portal.siemens.com/productcert/pdf/ssa-211752.pdfThird Party Advisory
- https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03757en_usThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K3EYJQHJZ2KTVQ7ICEFHXTLZ36MRASWX/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ORAMN3Q7TVJ54MBYF75XCJOE3DP7LYHT/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WNWGCQLW2VY72NIUYMJOCAKJKTXHDUK2/
- https://security.FreeBSD.org/advisories/FreeBSD-SA-16:24.ntp.ascThird Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.