Bug 1190294 (CVE-2012-6687)

Summary:	CVE-2012-6687 fcgi: numerous connections cause segfault DoS
Product:	[Other] Security Response	Reporter:	Kurt Seifried <kseifried>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	cweyl, kdreyer, opensource, sisharma, wmealing
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2015-08-25 05:55:47 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:	1189958, 1190212
Bug Blocks:	1190295

Description Kurt Seifried 2015-02-06 22:19:48 UTC

FCGI does not perform range checks for file descriptors before use of the FD_SET macro.  This FD_SET macro could allow for more than 1024 total file descriptors to be monitored in the closing state.

This may allow remote attackers to cause a denial of service (stack memory corruption, and infinite loop or daemon crash) by opening many socket connections to the host and crashing the service.

External references:
https://bugs.launchpad.net/ubuntu/+source/libfcgi/+bug/933417
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=681591

Upstream patches:

At this time the fcgi mailing list is down, this seems to be the patch that is chosen:

https://launchpadlibrarian.net/93064712/poll.patch

Comment 1 Ken Dreyer (Red Hat) 2015-02-06 22:31:22 UTC

link to CVE request: http://www.openwall.com/lists/oss-security/2015/02/06/4 (thanks Till for making the request)