CVE Vulnerabilities

CVE-2015-3405

Insufficient Entropy

Published: Aug 09, 2017 | Modified: Apr 20, 2025
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS 2.x
5 MEDIUM
AV:N/AC:L/Au:N/C:P/I:N/A:N
RedHat/V2
4 LOW
AV:N/AC:H/Au:N/C:P/I:P/A:N
RedHat/V3
Ubuntu
MEDIUM
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ntp-keygen in ntp 4.2.8px before 4.2.8p2-RC2 and 4.3.x before 4.3.12 does not generate MD5 keys with sufficient entropy on big endian machines when the lowest order byte of the temp variable is between 0x20 and 0x7f and not #, which might allow remote attackers to obtain the value of generated MD5 keys via a brute force attack with the 93 possible keys.

Weakness

The product uses an algorithm or scheme that produces insufficient entropy, leaving patterns or clusters of values that are more likely to occur than others.

Affected Software

NameVendorStart VersionEnd Version
NtpNtp4.2.8-p1 (including)4.2.8-p1 (including)
NtpNtp4.2.8-p2 (including)4.2.8-p2 (including)
NtpNtp4.2.8-p2-rc1 (including)4.2.8-p2-rc1 (including)
NtpNtp4.3.0 (including)4.3.0 (including)
NtpNtp4.3.1 (including)4.3.1 (including)
NtpNtp4.3.2 (including)4.3.2 (including)
NtpNtp4.3.3 (including)4.3.3 (including)
NtpNtp4.3.4 (including)4.3.4 (including)
NtpNtp4.3.5 (including)4.3.5 (including)
NtpNtp4.3.6 (including)4.3.6 (including)
NtpNtp4.3.7 (including)4.3.7 (including)
NtpNtp4.3.8 (including)4.3.8 (including)
NtpNtp4.3.9 (including)4.3.9 (including)
NtpNtp4.3.10 (including)4.3.10 (including)
NtpNtp4.3.11 (including)4.3.11 (including)
Red Hat Enterprise Linux 6RedHatntp-0:4.2.6p5-5.el6*
Red Hat Enterprise Linux 7RedHatntp-0:4.2.6p5-22.el7*
NtpUbuntuesm-infra-legacy/trusty*
NtpUbuntulucid*
NtpUbuntuprecise*
NtpUbuntutrusty*
NtpUbuntutrusty/esm*
NtpUbuntuupstream*
NtpUbuntuutopic*
NtpUbuntuvivid*

Potential Mitigations

References