Ensure to set Strong SSH KEY Exchange algorithm

中レベル 1自動f5-bigip

説明

To set strong Key Exchange algorithm PASS requires the sys sshd include statement to contain a KexAlgorithms line whose algorithms all use SHA-256 or stronger (e.g. diffie-hellman-group14-sha256). Audited against tmsh output with defaults shown: save the concatenated output of 'tmsh list auth password-policy all-properties', 'tmsh list auth source all-properties', 'tmsh list auth remote-user all-properties', 'tmsh list auth radius all-properties', 'tmsh list sys httpd all-properties', 'tmsh list sys sshd all-properties', 'tmsh list sys global-settings all-properties', 'tmsh list cli global-settings all-properties', 'tmsh list sys ntp', 'tmsh list sys snmp all-properties', 'tmsh list sys syslog' and 'tmsh list net self all-properties'. Patterns are scoped to the named top-level block.

チェック方法

監査方法: 設定パターン

パターン: (?ms)^sys sshd \{\n(?:[ \t]+[^\n]*\n)*?[ \t]+include \"[^\"]*\bKexAlgorithms (?:[\w@.-]*(?:sha256|sha384|sha512|sha2-nistp\d+|curve25519|curve448)[\w@.-]*,?)+\"?[ \t]*$

修正方法

修正方法: ガイダンスまたは IaC パッチ

tmsh modify sys sshd include "KexAlgorithms diffie-hellman-group14-sha256" (merge with any existing Ciphers/MACs lines in the same include string) tmsh save sys config # CIS guidance: 1-Log in to tmsh by typing the following command:tmsh 2-To modify the sshd configuration, type the following command to start the vi editor:edit /sys sshd all-properties 3-Set a Key-Exchange algorithm with key of size 256 or longer example diffie-hellman-group14-sha256) 4-To change the list of ciphers, you can navigate to the line that starts with the include statement, and use the keyword KexAlgorithms ,and adding the list of desired KexAlgorithms to the 2-line include statement: include "Ciphers aes128-cbc,aes128-ctr,aes192-ctr,aes256- ctr,arcfour128,arcfour256,arcfour MACs hmac-sha2-256 KexAlgorithms diffie-hellman-group14-sha256

プロパティ

オペレーティングシステム: すべて
タグ: f5-bigipcrypto
参照: CIS F5 Networks Benchmark v1.0.0 - 4.7 Ensure to set Strong SSH KEY Exchange algorithm

このホストをチェック

監査が許可されているマシンで実行してください。スキャンは読み取り専用です。

shell

tmaegis scan --target f5-bigip