Vulnerability Note VU#423396
X.509 certificate verification may be vulnerable to resource exhaustion
Some applications that perform X.509 certificate verification may be vulnerable to signature processing problems that lead to resource exhaustion. This vulnerability may cause a denial of service.
Included in X.509 certificates are public keys used for digital signature verification. Choosing very large values for the public exponent and public modulus associated with an RSA public key may cause the verification of that key to require large amounts of system resources. According to NISCC:
...by choosing much larger values for [the public exponent and the public modulus], it may be possible to cause the verification process to consume large amounts of system resources and hence result in a denial-of-service condition.
A remote, unauthenticated attacker could consume large amounts of system resources on an affected device, thereby creating a denial of service.
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Systems Affected (Learn More)
|Vendor||Status||Date Notified||Date Updated|
|Apple Computer, Inc.||Affected||-||04 Dec 2006|
|Avaya, Inc.||Affected||-||10 Nov 2006|
|Cisco Systems, Inc.||Affected||-||13 Nov 2006|
|Debian GNU/Linux||Affected||-||02 Oct 2006|
|FreeBSD, Inc.||Affected||-||28 Sep 2006|
|Gentoo Linux||Affected||-||19 Jan 2007|
|GnuTLS||Affected||-||28 Sep 2006|
|Hewlett-Packard Company||Affected||-||19 Jan 2007|
|Mandriva, Inc.||Affected||-||02 Oct 2006|
|OpenBSD||Affected||-||23 Oct 2006|
|OpenPKG||Affected||-||02 Oct 2006|
|OpenSSL||Affected||-||28 Sep 2006|
|Oracle Corporation||Affected||-||17 Jan 2007|
|Red Hat, Inc.||Affected||-||02 Oct 2006|
|rPath||Affected||-||06 Oct 2006|
CVSS Metrics (Learn More)
NISCC credits Dr. Stephen N. Henson for reporting this vulnerability. This issue was originally reported in GnuTLS by Patrik Hornik.
This document was written by Chris Taschner.
- CVE IDs: CVE-2006-2940
- Date Public: 02 Aug 2004
- Date First Published: 28 Sep 2006
- Date Last Updated: 09 Feb 2007
- Severity Metric: 7.92
- Document Revision: 62
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