Red Hat Bugzilla – Bug 169863
CAN-2005-2969 Potential SSL 2.0 Rollback
Last modified: 2007-11-30 17:07:20 EST
This text comes from the openssl advisory:
A vulnerability has been found in all previously released versions of
OpenSSL (all versions up to 0.9.7g, and version 0.9.8).
Versions 0.9.7h and 0.9.8a are being released to address the issue.
The vulnerability potentially affects applications that use the
SSL/TLS server implementation provided by OpenSSL.
Such applications are affected if they use the option
SSL_OP_MSIE_SSLV2_RSA_PADDING. This option is implied by use of
SSL_OP_ALL, which is intended to work around various bugs in
third-party software that might prevent interoperability. The
SSL_OP_MSIE_SSLV2_RSA_PADDING option disables a verification step in
the SSL 2.0 server supposed to prevent active protocol-version
rollback attacks. With this verification step disabled, an attacker
acting as a "man in the middle" can force a client and a server to
negotiate the SSL 2.0 protocol even if these parties both support SSL
3.0 or TLS 1.0. The SSL 2.0 protocol is known to have severe
cryptographic weaknesses and is supported as a fallback only.
Applications using neither SSL_OP_MSIE_SSLV2_RSA_PADDING nor
SSL_OP_ALL are not affected. Also, applications that disable
use of SSL 2.0 are not affected.
This issue also affects RHEL2.1 and RHEL3
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.