Scientific Linux: SLSA-2016:0372-1 Critical: OpenSSL Denial Of Service

Date: Wed, 9 Mar 2016 16:12:01 -0000
Reply-To: scientific-linux-users@
Sender: Security Errata for Scientific Linux
 
From: Pat Riehecky 
Subject: Security ERRATA Important: openssl098e on SL6.x, SL7.x i386/x86_64
MIME-Version: 1.0
Message-ID: <20160309161201.29476.25080@slpackages.fnal.gov>

Synopsis: Important: openssl098e security update
Advisory ID: SLSA-2016:0372-1
Issue Date: 2016-03-09
CVE Numbers: CVE-2015-0293
 CVE-2015-3197
 CVE-2016-0800
 CVE-2016-0703
 CVE-2016-0704
--

A padding oracle flaw was found in the Secure Sockets Layer version 2.0
(SSLv2) protocol. An attacker can potentially use this flaw to decrypt
RSA-encrypted cipher text from a connection using a newer SSL/TLS protocol
version, allowing them to decrypt such connections. This cross-protocol
attack is publicly referred to as DROWN. (CVE-2016-0800)

It was discovered that the SSLv2 servers using OpenSSL accepted SSLv2
connection handshakes that indicated non-zero clear key length for non-
export cipher suites. An attacker could use this flaw to decrypt recorded
SSLv2 sessions with the server by using it as a decryption
oracle.(CVE-2016-0703)

It was discovered that the SSLv2 protocol implementation in OpenSSL did
not properly implement the Bleichenbacher protection for export cipher
suites. An attacker could use a SSLv2 server using OpenSSL as a
Bleichenbacher oracle. (CVE-2016-0704)

Note: The CVE-2016-0703 and CVE-2016-0704 issues could allow for more
efficient exploitation of the CVE-2016-0800 issue via the DROWN attack.

A denial of service flaw was found in the way OpenSSL handled SSLv2
handshake messages. A remote attacker could use this flaw to cause a
TLS/SSL server using OpenSSL to exit on a failed assertion if it had both
the SSLv2 protocol and EXPORT-grade cipher suites enabled. (CVE-2015-0293)

A flaw was found in the way malicious SSLv2 clients could negotiate SSLv2
ciphers that have been disabled on the server. This could result in weak
SSLv2 ciphers being used for SSLv2 connections, making them vulnerable to
man-in-the-middle attacks. (CVE-2015-3197)

For the update to take effect, all services linked to the openssl098e
library must be restarted, or the system rebooted.
--

SL6
 x86_64
 openssl098e-0.9.8e-20.el6_7.1.i686.rpm
 openssl098e-0.9.8e-20.el6_7.1.x86_64.rpm
 openssl098e-debuginfo-0.9.8e-20.el6_7.1.i686.rpm
 openssl098e-debuginfo-0.9.8e-20.el6_7.1.x86_64.rpm
 i386
 openssl098e-0.9.8e-20.el6_7.1.i686.rpm
 openssl098e-debuginfo-0.9.8e-20.el6_7.1.i686.rpm
SL7
 x86_64
 openssl098e-0.9.8e-29.el7_2.3.i686.rpm
 openssl098e-0.9.8e-29.el7_2.3.x86_64.rpm
 openssl098e-debuginfo-0.9.8e-29.el7_2.3.i686.rpm
 openssl098e-debuginfo-0.9.8e-29.el7_2.3.x86_64.rpm

- Scientific Linux Development Team