GLSA 200510-11: OpenSSL: SSL 2.0 protocol rollback

http://security.gentoo.org/

Severity:	low
Title:	OpenSSL: SSL 2.0 protocol rollback
Date:	10/12/2005
Bugs:	#108852
ID:	200510-11

Synopsis

When using a specific option, OpenSSL can be forced to fallback to the less secure SSL 2.0 protocol.

Background

OpenSSL is a toolkit implementing the Secure Sockets Layer, Transport Layer Security protocols and a general-purpose cryptography library.

Affected packages

Package	Vulnerable	Unaffected	Architecture(s)
dev-libs/openssl	< 0.9.7h	>= 0.9.7h	All supported architectures

Description

Applications setting the SSL_OP_MSIE_SSLV2_RSA_PADDING option (or the SSL_OP_ALL option, that implies it) can be forced by a third-party to fallback to the less secure SSL 2.0 protocol, even if both parties support the more secure SSL 3.0 or TLS 1.0 protocols.

Impact

A man-in-the-middle attacker can weaken the encryption used to communicate between two parties, potentially revealing sensitive information.

Workaround

If possible, disable the use of SSL 2.0 in all OpenSSL-enabled applications.

Resolution

All OpenSSL users should upgrade to the latest version:

    # emerge --sync
    # emerge --ask --oneshot --verbose dev-libs/openssl

References

Availability

This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-200510-11.xml

Concerns?

Security is a primary focus of Gentoo Linux and ensuring the confidentiality and security of our users machines is of utmost importance to us. Any security concerns should be addressed to security@gentoo.org or alternatively, you may file a bug at https://bugs.gentoo.org.