Isolate BIND with chroot'ed Subdirectory

低级别 2自动化bind

说明

The chroot() system call causes an application to run with limited file system access so that a subdirectory becomes the root directory for the application environment. When this is done, the application is "jailed" and no longer has access to the entire file structure but is limited to the given subdirectory. The audit reads /proc/<named pid>/root and requires a chroot directory; SELinux in enforcing mode is accepted as the documented alternative.

检查方式

审计方法: Shell 命令

shell

pid=$(pidof named 2>/dev/null | awk '{print $1}')
[ -n "$pid" ] || { echo 'named is not running'; exit 1; }
r=$(readlink /proc/$pid/root) || exit 1
if [ "$r" != / ]; then echo compliant; elif [ "$(getenforce 2>/dev/null)" = Enforcing ]; then echo compliant; else echo 'named is not chrooted (and SELinux is not enforcing)'; fi

预期输出: compliant

修复方式

修复方法: 操作指南或基础设施补丁

Perform the following: ; Stop the named service and install the bind-chroot package to provide the chroot directories. # systemctl stop named.service # yum install bind-chroot ; Edit the /etc/sysconfig/named configuration file to have a line similar to the one shown below that sets the ROOTDIR environment variable. ROOTDIR="/var/named/chroot" ; Move all the configuration files and any master zone files into their respective directions under the subdirectory /var/named/chroot/

属性

操作系统: 任意
标签: binddnspermissions
参考: CIS ISC BIND DNS Server 9.11 Benchmark v1.0.0 - 2.9 Isolate BIND with chroot'ed Subdirectory

检查本机

请在您有权审计的机器上运行此命令。扫描为只读操作。

shell

tmaegis scan --target bind --level 2