The symmetric-key feature in the receive function in ntp_proto.c in...

Vulnerability Description

The symmetric-key feature in the receive function in ntp_proto.c in ntpd in NTP 4.x before 4.2.8p2 requires a correct MAC only if the MAC field has a nonzero length, which makes it easier for man-in-the-middle attackers to spoof packets by omitting the MAC.

References

• http://www.securitytracker.com/id/1032032
• http://www.ubuntu.com/usn/USN-2567-1
• http://www.kb.cert.org/vuls/id/374268
• http://marc.info/?l=bugtraq&m=143213867103400&w=2
• http://lists.fedoraproject.org/pipermail/package-announce/2015-April/155864.html
• http://support.ntp.org/bin/view/Main/SecurityNotice#Recent_Vulnerabilities
• https://kc.mcafee.com/corporate/index?page=content&id=SB10114
• http://lists.fedoraproject.org/pipermail/package-announce/2015-April/155863.html
• http://lists.apple.com/archives/security-announce/2015/Jun/msg00002.html
• http://lists.opensuse.org/opensuse-updates/2015-04/msg00052.html
• http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html
• https://security.gentoo.org/glsa/201509-01
• http://tools.cisco.com/security/center/viewAlert.x?alertId=38276
• http://marc.info/?l=bugtraq&m=143213867103400&w=2
• http://www.mandriva.com/security/advisories?name=MDVSA-2015:202
• http://www.oracle.com/technetwork/topics/security/bulletinapr2015-2511959.html
• http://www.securityfocus.com/bid/73951
• http://support.apple.com/kb/HT204942
• http://rhn.redhat.com/errata/RHSA-2015-1459.html
• http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20150408-ntpd
• http://bugs.ntp.org/show_bug.cgi?id=2779
• http://www.debian.org/security/2015/dsa-3223