OpenSSL, AMD64 x86 emulation base libraries: RSA signature forgery

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Updated September 07, 2006

1.  Gentoo Linux Security Advisory

Version Information

Advisory Reference GLSA 200609-05 / openssl
Release Date September 07, 2006
Latest Revision September 08, 2006: 02
Impact normal
Exploitable remote
Package Vulnerable versions Unaffected versions Architecture(s)
dev-libs/openssl < 0.9.7k >= 0.9.7k All supported architectures
app-emulation/emul-linux-x86-baselibs < 2.5.2 >= 2.5.2 AMD64

Related bugreports: #146375, #146438

Synopsis

OpenSSL fails to properly validate PKCS #1 v1.5 signatures.

2.  Impact Information

Background

OpenSSL is a toolkit implementing the Secure Sockets Layer, Transport Layer Security protocols and a general-purpose cryptography library. The x86 emulation base libraries for AMD64 contain a vulnerable version of OpenSSL.

Description

Daniel Bleichenbacher discovered that it might be possible to forge signatures signed by RSA keys with the exponent of 3.

Impact

Since several CAs are using an exponent of 3 it might be possible for an attacker to create a key with a false CA signature.

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-0.9.7k"

All AMD64 x86 emulation base libraries users should upgrade to the latest version:

Code Listing 3.2: Resolution

# emerge --sync
# emerge --ask --oneshot --verbose ">=app-emulation/emul-linux-x86-baselibs-2.5.2"

4.  References