bash注入漏洞(CVE-2014-6271)

Filed Under: 技术 by admin

Sep.26, 2014

检测代码
env x='() { :;}; echo vulnerable' bash -c "echo this is a test"
出现 vulnerable

漏洞描述
Bash Code Injection Vulnerability (CVE-2014-6271)

Published Wednesday at 5:34 PM
Red Hat Product Security has been made aware of a vulnerability affecting all versions of the bash package shipped with Red Hat Enterprise Linux. Since many of Red Hat's products run on a base installation of Red Hat Enteprise Linux, there is a risk of other products being impacted by this vulnerability as well.

The bash code injection vulnerability CVE-2014-6271 could allow for arbitrary code execution, allowing an attacker to bypass imposed environment restrictions. Certain services and applications allow remote unauthenticated attackers to exploit this vulnerability by providing environment variables. As the Bash shell is the most commonly used shell today, the risk of impact from this vulnerability if left unchecked could be severe.

To learn more about affected products, remediation steps, and testing your Bash version for vulnerabilities, see https://access.redhat.com/articles/1200223 in the Red Hat Customer Portal.

If you have questions or concerns, please contact Red Hat Technical Support.
解决方案
请您根据Linux版本选择您需要修复的命令，为了防止意外情况发生，建议您执行命令前先对Linux服务器系统盘打个快照，如果万一出现升级影响您服务器使用情况，可以通过回滚系统盘快照解决。

centos:(最终解决方案)
yum clean all
yum makecache
yum -y update bash

ubuntu:(最终解决方案)
apt-cache gencaches
apt-get -y install --only-upgrade bash

debian:(最终解决方案)
7.5 64bit && 32bit
apt-cache gencaches
apt-get -y install --only-upgrade bash

6.0.x 64bit
wget http://mirrors.aliyun.com/debian/pool/main/b/bash/bash_4.1-3+deb6u2_amd64.deb && dpkg -i bash_4.1-3+deb6u2_amd64.deb

6.0.x 32bit
wget http://mirrors.aliyun.com/debian/pool/main/b/bash/bash_4.1-3+deb6u2_i386.deb && dpkg -i bash_4.1-3+deb6u2_i386.deb

aliyun linux:(最终解决方案)
5.x 64bit
wget http://mirrors.aliyun.com/centos/5/updates/x86_64/RPMS/bash-3.2-33.el5_10.4.x86_64.rpm && rpm -Uvh bash-3.2-33.el5_10.4.x86_64.rpm

5.x 32bit
wget http://mirrors.aliyun.com/centos/5/updates/i386/RPMS/bash-3.2-33.el5_10.4.i386.rpm && rpm -Uvh bash-3.2-33.el5_10.4.i386.rpm

opensuse:(官方还没有给出最终解决方案，该方案存在被绕过的风险，阿里云会第一时间更新，请继续关注)
13.1 64bit
wget http://mirrors.aliyun.com/fix_stuff/bash-4.2-68.4.1.x86_64.rpm && rpm -Uvh bash-4.2-68.4.1.x86_64.rpm

13.1 32bit
wget http://mirrors.aliyun.com/fix_stuff/bash-4.2-68.4.1.i586.rpm && rpm -Uvh bash-4.2-68.4.1.i586.rpm