OpenSSL: Certificate validation error

Security Team  Contact Address

Updated February 12, 2009

1.  Gentoo Linux Security Advisory

Version Information

Advisory Reference GLSA 200902-02 / openssl
Release Date February 12, 2009
Latest Revision February 12, 2009: 01
Impact normal
Exploitable remote
Package Vulnerable versions Unaffected versions Architecture(s)
dev-libs/openssl < 0.9.8j >= 0.9.8j All supported architectures

Related bugreports: #251346

Synopsis

An error in the OpenSSL certificate chain validation might allow for spoofing attacks.

2.  Impact Information

Background

OpenSSL is an Open Source toolkit implementing the Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1) as well as a general purpose cryptography library.

Description

The Google Security Team reported that several functions incorrectly check the result after calling the EVP_VerifyFinal() function, allowing a malformed signature to be treated as a good signature rather than as an error. This issue affects the signature checks on DSA and ECDSA keys used with SSL/TLS.

Impact

A remote attacker could exploit this vulnerability and spoof arbitrary names to conduct Man-In-The-Middle attacks and intercept sensitive information.

3.  Resolution Information

Workaround

There is no known workaround at this time.

Resolution

All OpenSSL users should upgrade to the latest version:

Code Listing 3.1: Resolution

# emerge --sync
# emerge --ask --oneshot --verbose ">=dev-libs/openssl-0.9.8j"

4.  References