Bug 1331466 (CVE-2016-2516)

Summary:	CVE-2016-2516 ntp: assertion failure in ntpd on duplicate IPs on unconfig directives
Product:	[Other] Security Response	Reporter:	Martin Prpič <mprpic>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	jaeshin, mlichvar, sardella, slawomir
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	ntp 4.2.8p7	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2016-05-02 12:56:01 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1332160
Bug Blocks:	1331437

Description Martin Prpič 2016-04-28 14:52:50 UTC

The following flaw was found in ntpd:

If ntpd was expressly configured to allow for remote configuration, a malicious user who knows the controlkey for ntpq or the requestkey for ntpdc (if mode7 is expressly enabled) can create a session with ntpd and if an existing association is unconfigured using the same IP twice on the unconfig directive line, ntpd will abort.

Upstream bugs:

http://support.ntp.org/bin/view/Main/NtpBug3011

External References:

http://support.ntp.org/bin/view/Main/SecurityNotice#April_2016_NTP_4_2_8p7_Security

Comment 1 Martin Prpič 2016-05-02 11:37:40 UTC

Created ntp tracking bugs for this issue:

Affects: fedora-all [bug 1332160]

Comment 2 Martin Prpič 2016-05-02 12:56:01 UTC

Mitigation:

Disable remote configuration of NTP, or restrict this ability to trusted users.

Comment 3 Fedora Update System 2016-05-07 11:42:11 UTC

ntp-4.2.6p5-40.fc24 has been pushed to the Fedora 24 stable repository. If problems still persist, please make note of it in this bug report.

Comment 4 Fedora Update System 2016-05-10 17:58:37 UTC

ntp-4.2.6p5-40.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.

Comment 5 Fedora Update System 2016-05-12 07:21:45 UTC

ntp-4.2.6p5-40.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.