Vulnerability Note VU#335392

The Mozilla Network Security Services library fails to properly verify RSA signatures

Original Release date: 08 Nov 2006 | Last revised: 23 Jan 2007

Overview

The Mozilla Network Security Services library fails to properly verify RSA signatures. This vulnerability may allow an attacker to forge RSA signatures.

Description

RSA signatures are used to authenticate the source of a message. To prevent RSA signatures from being forged, messages are padded with data to ensure message hashes are adequately sized. The Mozilla Network Security Services (NSS) library fails to properly verify the padding in RSA signatures, ignoring data at the end of a signature. If this data is ignored and an RSA key with a public exponent of three is used, it may be possible to forge the signing key's signature.

For more information refer to Mozilla Foundation Security Advisory 2006-66.

This vulnerability may affect any application that uses the Mozilla NSS librbary, including SSL/TLS and email certificates.

Impact

This vulnerability may allow an attacker to forge an RSA signature.

Solution

Apply an update
According to the Mozilla Foundation Security Advisory 2006-66, this vulnerability is addressed in Firefox 1.5.0.8, Thunderbird 1.5.0.8, and SeaMonkey 1.0.6.

Note that according to Mozilla:

    Firefox 1.5.0.x will be maintained with security and stability updates until April 24, 2007. All users are strongly encouraged to upgrade to Firefox 2.

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
Apple Computer, Inc.Affected-08 Jan 2007
Blue Coat SystemsAffected-08 Jan 2007
MozillaAffected06 Nov 200608 Nov 2006
RSA Security, Inc.Affected-18 Dec 2006
SybaseAffected-08 Jan 2007
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A

References

Credit

This vulnerability was reported in Mozilla Foundation Security Advisory 2006-66. Mozilla credits Ulrich Kuehn for providing information concerning this issue.

This document was written by Chris Taschner.

Other Information

  • CVE IDs: CVE-2006-5462
  • Date Public: 08 Nov 2006
  • Date First Published: 08 Nov 2006
  • Date Last Updated: 23 Jan 2007
  • Severity Metric: 7.56
  • Document Revision: 47

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