Bug 1578593 (CVE-2018-5737)

Summary:	CVE-2018-5737 bind: Interaction between NSEC aggresive negative caching and the serve-stale feature can cause a denial of service
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, dbaker, jokerman, jpopelka, mruprich, msehnout, pemensik, pzhukov, security-response-team, sfowler, sthangav, thozza, trankin, vonsch, yozone, zdohnal
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	bind 9.12.1-P2	Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in the "serve-stale" feature as implemented in bind. Problematic interaction between serve-stale feature and NSEC aggressive negative caching could cause denial of service.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2018-05-17 04:02:18 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:	1578904
Bug Blocks:	1578592

Description Sam Fowler 2018-05-16 00:01:43 UTC

BIND versions 9.12.0 and 9.12.1 are vulnerable to problematic interaction between the serve-stale feature and NSEC aggressive negative caching can in some cases cause undesirable behavior from named, such as a recursion loop or an assertion failure resulting in termination of the named process.

Deliberate exploitation of this condition could cause operational problems depending on the particular manifestation -- either degradation or denial of service.

Comment 2 Huzaifa S. Sidhpurwala 2018-05-17 04:01:02 UTC

Statement:

This security flaw only affects bind versions 9.12.0 and 9.12.1. Since Red Hat Enterprise Linux does not ship any of these bind versions, it is not affected.

Comment 3 Sam Fowler 2018-05-20 23:48:13 UTC

External Reference:

https://kb.isc.org/article/AA-01606/74/CVE-2018-5737


Upstream Patch:

https://ftp.isc.org/isc/bind9/9.12.1-P2/patches/cve5737.patch