[ GLSA 200510-11 ] OpenSSL: SSL 2.0 protocol rollback

[GLSA]

Gentoo Linux Security Advisory

Title: OpenSSL: SSL 2.0 protocol rollback (GLSA 200510-11)
Severity: low
Exploitable: remote
Date: October 12, 2005
Updated: November 07, 2005
Bug(s): #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: dev-libs/openssl
Vulnerable: < 0.9.7h
Unaffected: >= 0.9.7h
Unaffected: >= 0.9.7g-r1 < 0.9.8
Unaffected: >= 0.9.7e-r2 < 0.9.8
Architectures: 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: