Mandrake Linux Security Advisory : openssl (MDKSA-2005:179)

Medium Nessus Plugin ID 20039


The remote Mandrake Linux host is missing one or more security updates.


Yutaka Oiwa discovered 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.

The current default algorithm for creating 'message digests' (electronic signatures) for certificates created by openssl is MD5.
However, this algorithm is not deemed secure any more, and some practical attacks have been demonstrated which could allow an attacker to forge certificates with a valid certification authority signature even if he does not know the secret CA signing key.

To address this issue, openssl has been changed to use SHA-1 by default. This is a more appropriate default algorithm for the majority of use cases. If you still want to use MD5 as default, you can revert this change by changing the two instances of 'default_md = sha1' to 'default_md = md5' in /usr/{lib,lib64}/ssl/openssl.cnf.


Update the affected packages.

Plugin Details

Severity: Medium

ID: 20039

File Name: mandrake_MDKSA-2005-179.nasl

Version: $Revision: 1.16 $

Type: local

Published: 2005/10/19

Modified: 2013/05/31

Dependencies: 12634

Risk Information

Risk Factor: Medium


Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N

Vulnerability Information

CPE: p-cpe:/a:mandriva:linux:lib64openssl0.9.7, p-cpe:/a:mandriva:linux:lib64openssl0.9.7-devel, p-cpe:/a:mandriva:linux:lib64openssl0.9.7-static-devel, p-cpe:/a:mandriva:linux:libopenssl0.9.7, p-cpe:/a:mandriva:linux:libopenssl0.9.7-devel, p-cpe:/a:mandriva:linux:libopenssl0.9.7-static-devel, p-cpe:/a:mandriva:linux:openssl, cpe:/o:mandrakesoft:mandrake_linux:10.1, cpe:/o:mandriva:linux:2006, x-cpe:/o:mandrakesoft:mandrake_linux:le2005

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/Mandrake/release, Host/Mandrake/rpm-list

Patch Publication Date: 2005/10/11

Reference Information

CVE: CVE-2005-2946, CVE-2005-2969

MDKSA: 2005:179

CWE: 310