Bug 1589616 (CVE-2018-5738)

Summary:	CVE-2018-5738 bind: Improper handling of configuration allows all clients to perform recursive queries
Product:	[Other] Security Response	Reporter:	Sam Fowler <sfowler>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	abhgupta, anon.amish, dbaker, jokerman, jpopelka, mruprich, msehnout, pemensik, pzhukov, security-response-team, sthangav, thozza, trankin, vonsch, yozone, zdohnal
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-06-10 10:28:33 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:	1590578, 1590579, 1590580
Bug Blocks:	1589617

Description Sam Fowler 2018-06-11 01:13:19 UTC

BIND was found to not properly handle certain configuration options, unintentionally permiting all clients to perform recursive queries. This occurs when "recursion yes;" is in effect and no match list values are provided for "allow-query-cache" or "allow-query" for the setting of "allow-recursion" to inherit a setting of all hosts from the "allow-query" setting default.

The permitting of recursive queries to unauthorized clients can allow for:
* Increase the load on a server, possibly degrading service to authorized clients.
* A server to being co-opted for use in DNS reflection attacks.
* An attacker may be able to deduce which queries a server has previously serviced by examining the results of queries answered from the cache, potentially leaking private information about what queries have been performed.

This affects the following versions:
* 9.9.12
* 9.10.7
* 9.11.3
* 9.12.0 to 9.12.1-P2
* 9.13.0

Comment 5 Tomas Hoger 2018-06-12 07:04:09 UTC

The flaw was introduced via the following upstream commit:

https://source.isc.org/cgi-bin/gitweb.cgi?p=bind9.git;a=commitdiff;h=89636d8f305956ad42e95a988502c7345e85ffe1

This change has not yet been included in any bind in Red Hat Enterprise Linux.

Comment 6 Sam Fowler 2018-06-13 00:17:55 UTC

External Reference:

https://kb.isc.org/article/AA-01616/0/CVE-2018-5738

Comment 7 Sam Fowler 2018-06-13 00:20:35 UTC

Acknowledgments:

Name: ISC

Comment 8 Sam Fowler 2018-06-13 00:21:56 UTC

Created bind tracking bugs for this issue:

Affects: fedora-all [bug 1590580]


Created bind99 tracking bugs for this issue:

Affects: fedora-all [bug 1590579]