Debian DSA-3223-1 : ntp - security update

Medium Nessus Plugin ID 82745

Synopsis

The remote Debian host is missing a security-related update.

Description

Multiple vulnerabilities were discovered in ntp, an implementation of the Network Time Protocol :

- CVE-2015-1798 When configured to use a symmetric key with an NTP peer, ntpd would accept packets without MAC as if they had a valid MAC. This could allow a remote attacker to bypass the packet authentication and send malicious packets without having to know the symmetric key.

- CVE-2015-1799 When peering with other NTP hosts using authenticated symmetric association, ntpd would update its internal state variables before the MAC of the NTP messages was validated. This could allow a remote attacker to cause a denial of service by impeding synchronization between NTP peers.

Additionally, it was discovered that generating MD5 keys using ntp-keygen on big endian machines would either trigger an endless loop, or generate non-random keys.

Solution

Upgrade the ntp packages.

For the stable distribution (wheezy), these problems have been fixed in version 1:4.2.6.p5+dfsg-2+deb7u4.

For the stable distribution (jessie), these problems have been fixed in version 1:4.2.6.p5+dfsg-7.

See Also

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=782095

https://security-tracker.debian.org/tracker/CVE-2015-1798

https://security-tracker.debian.org/tracker/CVE-2015-1799

https://packages.debian.org/source/wheezy/ntp

https://packages.debian.org/source/jessie/ntp

https://www.debian.org/security/2015/dsa-3223

Plugin Details

Severity: Medium

ID: 82745

File Name: debian_DSA-3223.nasl

Version: 1.9

Type: local

Agent: unix

Published: 2015/04/14

Updated: 2018/11/10

Dependencies: 12634

Risk Information

Risk Factor: Medium

CVSS v2.0

Base Score: 5

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N

Temporal Vector: CVSS2#E:U/RL:OF/RC:C

CVSS v3.0

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:debian:debian_linux:ntp, cpe:/o:debian:debian_linux:7.0, cpe:/o:debian:debian_linux:8.0

Required KB Items: Host/local_checks_enabled, Host/Debian/release, Host/Debian/dpkg-l

Exploit Available: false

Exploit Ease: No known exploits are available

Patch Publication Date: 2015/04/12

Reference Information

CVE: CVE-2015-1798, CVE-2015-1799, CVE-2015-3405

DSA: 3223