Bug 605789 (CVE-2010-2192)

Summary:	CVE-2010-2192 pmount: symlink attacks via lockfile files
Product:	[Other] Security Response	Reporter:	Vincent Danen <vdanen>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	Keywords:	Security
Target Milestone:	---
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Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2010-06-18 19:03:16 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:

Description Vincent Danen 2010-06-18 18:57:46 UTC

Common Vulnerabilities and Exposures assigned an identifier CVE-2010-2192 to
the following vulnerability:

Name: CVE-2010-2192
URL: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2010-2192
Assigned: 20100607
Reference: CONFIRM: http://security.debian.org/pool/updates/main/p/pmount/pmount_0.9.18-2+lenny1.diff.gz
Reference: DEBIAN:DSA-2063
Reference: URL: http://www.debian.org/security/2010/dsa-2063

The make_lockdir_name function in policy.c in pmount 0.9.18 allow
local users to overwrite arbitrary files via a symlink attack on a
file in /var/lock/.


This bug was reported to Ubuntu [1].  The entire premise of this vulnerability requires /var/lock be world-writable (in Debian and Ubuntu /var/lock is world-writable with a sticky bit).  In Fedora and Red Hat Enterprise Linux, /var/lock is not world-writable (mode 0775, owned root:lock), so users would not be able to create arbitrary files or symlinks in /var/lock.

The patch [2] used to correct the flaw moves the pmount lock directory from /var/lock/pmount/ to /var/lib/pmount-locks/ which is presumably not a world-writable directory, but does not change anything else.

I am not convinced we need to adopt this patch, it looks pretty Debian/Ubuntu-specific.

[1] https://bugs.launchpad.net/ubuntu/+source/pmount/+bug/574809
[2] http://launchpadlibrarian.net/50504393/fix-pmount-var-lock-exploit-v2.diff

Comment 1 Vincent Danen 2010-06-18 19:03:16 UTC

I'm closing this as NOTABUG because the referenced patch does what we already (correctly) do.