How To Patch and Protect OpenSSL Vulnerability # CVE-2015-0291 CVE-2015-0204 [ 19/March/2015 ]
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n 19th March 2015, multiple high and moderate severity level vulnerabilities released in OpenSSL, a Secure Sockets Layer toolkit used in a Linux and Unix-like systems. How can I fix these vulnerabilities on a CentOS/RHEL/Ubuntu and Debian Linux based server for OpenSSL versions 1.0.2a, 1.0.1m, 1.0.0r, and 0.9.8zf.? How do I verify that my Linux server has been fixed against the OpenSSL vulnerability?
A serious security problem has been found and patched in the OpenSSL Library. Multiple vulnerabilities have been discovered in OpenSSL on 19/March/2015. The Common Vulnerabilities and exposures project identifies the following issues:
OpenSSL 1.0.2 ClientHello sigalgs DoS (CVE-2015-0291) – Severity: High
Reclassified: RSA silently downgrades to EXPORT_RSA [Client] (CVE-2015-0204) – Severity: High
Multiblock corrupted pointer (CVE-2015-0290) – Severity: Moderate
Segmentation fault in DTLSv1_listen (CVE-2015-0207) – Severity: Moderate
Segmentation fault in ASN1_TYPE_cmp (CVE-2015-0286) – Severity: Moderate
Segmentation fault for invalid PSS parameters (CVE-2015-0208) – Severity: Moderate
ASN.1 structure reuse memory corruption (CVE-2015-0287) – Severity: Moderate
PKCS7 NULL pointer dereferences (CVE-2015-0289) – Severity: Moderate
Base64 decode (CVE-2015-0292) – Severity: Moderate
DoS via reachable assert in SSLv2 servers (CVE-2015-0293) – Severity: Moderate
Empty CKE with client auth and DHE (CVE-2015-1787) – Severity: Moderate
Handshake with unseeded PRNG (CVE-2015-0285) – Severity: Low
Use After Free following d2i_ECPrivatekey error (CVE-2015-0209) Severity: Low
X509_to_X509_REQ NULL pointer deref (CVE-2015-0288) Severity: Low
How bad will this actually be?
It is not bad as the heartbleed openssl bug disclosed in April 2014 in the OpenSSL cryptography library. But, new bug can cause “Denial of Service” and crash your services. It is good security practice, to quickly apply the patched version on your system and restart the affected services.
How to find openssl version on a Linux?
The syntax is as follows:
Find openssl version on a CentOS/RHEL/SL/Fedora Linux
openssl version
or ##
sudo yum list installed openssl
Sample outputs:
Fig.01: How to RHEL/CentOS/Fedora Linux Find OpenSSL Version Command
Find openssl version on a Debian/Ubuntu Linux
openssl version
or ##
sudo dpkg -l | egrep ^ii.*openssl
Sample outputs:
Fig.02: How to Debian/Ubuntu Linux Find OpenSSL Version Command
A list of affected Linux distros
I recommend that you upgrade your openssl packages ASAP to avoid any security issues on both client and server systems powered by Linux based distro.
RHEL version 6.x
RHEL version 7.x
CentoS Linux version 6.x
CentoS Linux version 7.x
Debian Linux stable (wheezy) 7.x
Ubuntu Linux 14.10
Ubuntu Linux 14.04 LTS
Ubuntu Linux 12.04 LTS
Ubuntu Linux 10.04 LTS
How to patch on a Linux?
Type the following commands as per your distro version/type:
how do I find out my distro version? ##
lsb_release -a
or use ##
cat /etc/*-release
Sample outputs:
Gif 01: HowTo: Find Out My Linux Distribution Name and Version
CentOS/RHEL/Fedora Linux
Type the following yum command to patch openssl as root user to patch openssl:
sudo yum clean all
To install the updates, use the yum command as follows:
sudo yum update
To only update the OpenSSL package and its dependencies, use the following yum command:
sudo yum update openssl
Sample outputs:
Loaded plugins: auto-update-debuginfo, protectbase, rhnplugin, security
This system is receiving updates from RHN Classic or RHN Satellite.
Setting up Update Process
epel-debuginfo/metalink | 13 kB 00:00
rhel-x86_64-server-6 | 1.5 kB 00:00
rhel-x86_64-server-6/primary | 21 MB 00:05
rhel-x86_64-server-6 14680/14680
rhel-x86_64-server-6-debuginfo | 1.3 kB 00:00
rhel-x86_64-server-6-debuginfo/primary | 1.1 MB 00:00
rhel-x86_64-server-6-debuginfo 5939/5939
rhel-x86_64-server-optional-6 | 1.5 kB 00:00
rhel-x86_64-server-optional-6/primary | 2.0 MB 00:00
rhel-x86_64-server-optional-6 8239/8239
rhel-x86_64-server-optional-6-debuginfo | 1.3 kB 00:00
rhel-x86_64-server-optional-6-debuginfo/primary | 681 kB 00:00
rhel-x86_64-server-optional-6-debuginfo 3571/3571
0 packages excluded due to repository protections
Resolving Dependencies
–> Running transaction check
—> Package openssl.x86_64 0:1.0.1e-30.el6_6.5 will be updated
–> Processing Dependency: openssl = 1.0.1e-30.el6_6.5 for package: openssl-devel-1.0.1e-30.el6_6.5.x86_64
—> Package openssl.x86_64 0:1.0.1e-30.el6_6.7 will be an update
–> Running transaction check
—> Package openssl-devel.x86_64 0:1.0.1e-30.el6_6.5 will be updated
—> Package openssl-devel.x86_64 0:1.0.1e-30.el6_6.7 will be an update
–> Finished Dependency Resolution
Dependencies Resolved
================================================================================
Package Arch Version Repository Size
================================================================================
Updating:
openssl x86_64 1.0.1e-30.el6_6.7 rhel-x86_64-server-6 1.5 M
Updating for dependencies:
openssl-devel x86_64 1.0.1e-30.el6_6.7 rhel-x86_64-server-6 1.2 M
Transaction Summary
================================================================================
Upgrade 2 Package(s)
Total download size: 2.7 M
Is this ok [y/N]: n
Exiting on user Command
[root@txvip1 ~]#
[root@txvip1 ~]# yum update openssl
Loaded plugins: auto-update-debuginfo, protectbase, rhnplugin, security
This system is receiving updates from RHN Classic or RHN Satellite.
Setting up Update Process
0 packages excluded due to repository protections
Resolving Dependencies
–> Running transaction check
—> Package openssl.x86_64 0:1.0.1e-30.el6_6.5 will be updated
–> Processing Dependency: openssl = 1.0.1e-30.el6_6.5 for package: openssl-devel-1.0.1e-30.el6_6.5.x86_64
—> Package openssl.x86_64 0:1.0.1e-30.el6_6.7 will be an update
–> Running transaction check
—> Package openssl-devel.x86_64 0:1.0.1e-30.el6_6.5 will be updated
—> Package openssl-devel.x86_64 0:1.0.1e-30.el6_6.7 will be an update
–> Finished Dependency Resolution
Dependencies Resolved
============================================================================================
Package Arch Version Repository Size
============================================================================================
Updating:
openssl x86_64 1.0.1e-30.el6_6.7 rhel-x86_64-server-6 1.5 M
Updating for dependencies:
openssl-devel x86_64 1.0.1e-30.el6_6.7 rhel-x86_64-server-6 1.2 M
Transaction Summary
============================================================================================
Upgrade 2 Package(s)
Total download size: 2.7 M
Is this ok [y/N]: y
Downloading Packages:
(1/2): openssl-1.0.1e-30.el6_6.7.x86_64.rpm | 1.5 MB 00:00
(2/2): openssl-devel-1.0.1e-30.el6_6.7.x86_64.rpm | 1.2 MB 00:00
Total 6.4 MB/s | 2.7 MB 00:00
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
Updating : openssl-1.0.1e-30.el6_6.7.x86_64 1/4
Updating : openssl-devel-1.0.1e-30.el6_6.7.x86_64 2/4
Cleanup : openssl-devel-1.0.1e-30.el6_6.5.x86_64 3/4
Cleanup : openssl-1.0.1e-30.el6_6.5.x86_64 4/4
Verifying : openssl-1.0.1e-30.el6_6.7.x86_64 1/4
Verifying : openssl-devel-1.0.1e-30.el6_6.7.x86_64 2/4
Verifying : openssl-1.0.1e-30.el6_6.5.x86_64 3/4
Verifying : openssl-devel-1.0.1e-30.el6_6.5.x86_64 4/4
Updated:
openssl.x86_64 0:1.0.1e-30.el6_6.7
Dependency Updated:
openssl-devel.x86_64 0:1.0.1e-30.el6_6.7
Complete!
Debian/Ubuntu Linux
Type the following apt-get commands to patch openssl as root user to patch openssl:
sudo apt-get update
sudo apt-get upgrade
Sample outputs:
Fig.04: OpenSSL patched on a Ubuntu Linux
Do I need to reboot my server/laptop/computer powered by Linux?
Short answer – yes, you need to reboot your computer/server to make all the necessary changes. Sysadmin should plan on updating as soon as possible or use maintenance reboot window:
sudo reboot
Long answer – It depends. You can avoid reboot by restarting required services. Fist, find all services that depend on the OpenSSL libraries, and restart them one-by-one using the service command:
Debian/Ubuntu find out if service needed reboot ##
checkrestart -v
Generic method ##
lsof | grep libssl | awk {print $1} | sort | uniq
Sample outputs:
hhvm
mysqld
nginx
php5-fpm
Restart the above services one-by-one, run:
sudo service restart hhvm restart
sudo service restart mysqld restart
sudo service restart nginx restart
sudo service restart php5-fpm restart
References
OpenSSL Security Advisory [19 Mar 2015]
DSA-3197-1 openssl — security update
USN-2537-1: OpenSSL vulnerabilities
OpenSSL Updates of 19 March 2015
LibreSSL addresses a number of security issues in coordination with the OpenSSL project released on 19 March 2015
