CVE-2016-4953

HIGH

Ntp < 4.2.8 - Authentication Bypass

Title source: rule

Description

ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (ephemeral-association demobilization) by sending a spoofed crypto-NAK packet with incorrect authentication data at a certain time.

References (32)

[Issue Tracking, Vendor Advisory] http://bugs.ntp.org/3045

[Mailing List, Third Party Advisory] http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00018.html

[Mailing List] http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00020.html

[Mailing List, Third Party Advisory] http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00023.html

[Mailing List, Third Party Advisory] http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00024.html

[Mailing List, Third Party Advisory] http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00028.html

[Mailing List, Third Party Advisory] http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00040.html

[Mailing List] http://lists.opensuse.org/opensuse-security-announce/2016-07/msg00026.html

[Mailing List] http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00042.html

[Exploit, Third Party Advisory] http://packetstormsecurity.com/files/137321/Slackware-Security-Advisory-ntp-Updates.html

[Exploit, Third Party Advisory] http://packetstormsecurity.com/files/137322/FreeBSD-Security-Advisory-FreeBSD-SA-16-24.ntp.html

[Patch, Vendor Advisory] http://support.ntp.org/bin/view/Main/NtpBug3045

[Vendor Advisory] http://support.ntp.org/bin/view/Main/SecurityNotice

[Various Sources] http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160603-ntpd

[Third Party Advisory, US Government Resource] http://www.kb.cert.org/vuls/id/321640

[Third Party Advisory] http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html

[Third Party Advisory, VDB Entry] http://www.securityfocus.com/bid/91010

[Third Party Advisory, VDB Entry] http://www.securitytracker.com/id/1036037

[Third Party Advisory] https://cert-portal.siemens.com/productcert/pdf/ssa-211752.pdf

[Third Party Advisory] https://cert-portal.siemens.com/productcert/pdf/ssa-497656.pdf

... and 12 more

Scores

CVSS v3 7.5

EPSS 0.1437

EPSS Percentile 94.3%

Attack Vector NETWORK

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Classification

CWE

CWE-287

Status draft

Affected Products (37)

ntp/ntp < 4.2.8

ntp/ntp

... and 22 more

Timeline

Published Jul 05, 2016

Tracked Since Feb 18, 2026