Bug 1550214 (CVE-2018-7170) - CVE-2018-7170 ntp: Ephemeral association time spoofing additional protection
Summary: CVE-2018-7170 ntp: Ephemeral association time spoofing additional protection
Alias: CVE-2018-7170
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
Depends On: 1550228 1550229 1561056 1582246
Blocks: 1550226 1658223
TreeView+ depends on / blocked
Reported: 2018-02-28 19:37 UTC by Pedro Sampaio
Modified: 2021-12-10 15:44 UTC (History)
5 users (show)

Fixed In Version: ntp 4.2.8p11
Doc Type: If docs needed, set a value
Doc Text:
A flaw was found in ntpd making it vulnerable to Sybil attacks. An authenticated attacker could target systems configured to use a trusted key in certain configurations and to create an arbitrary number of associations and subsequently modify a victim's clock.
Clone Of:
Last Closed: 2021-10-21 19:56:49 UTC

Attachments (Terms of Use)

Description Pedro Sampaio 2018-02-28 19:37:48 UTC
ntpd can be vulnerable to Sybil attacks. If a system is set up to use a trustedkey and if one is not using the feature introduced in ntp-4.2.8p6 allowing an optional 4th field in the ntp.keys file to specify which IPs can serve time, a malicious authenticated peer -- i.e. one where the attacker knows the private symmetric key -- can create arbitrarily-many ephemeral associations in order to win the clock selection of ntpd and modify a victim's clock.

Ps.: This is possibly a incomplete fix for CVE-2016-1549.



Comment 1 Pedro Sampaio 2018-02-28 19:51:45 UTC
Created ntp tracking bugs for this issue:

Affects: fedora-all [bug 1550228]

Note You need to log in before you can comment on or make changes to this bug.