From 8bf82a98ae80879d2b1800ae0d5bc19b6c5cab3c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Mat=C4=9Bj=20T=C3=BD=C4=8D?= Date: Thu, 14 Nov 2019 18:04:39 +0100 Subject: [PATCH 1/2] Fix RHEL7 rules sshd_use_strong_macs and sshd_use_strong_ciphers. - Implemented Bash remediations according to rule description. - Synced sshd_use_strong_ciphers OVAL according with the rule description. --- .../ssh/ssh_server/sshd_use_strong_ciphers/bash/shared.sh | 3 +++ .../ssh/ssh_server/sshd_use_strong_ciphers/oval/shared.xml | 2 +- .../ssh/ssh_server/sshd_use_strong_macs/bash/shared.sh | 4 ++++ 3 files changed, 8 insertions(+), 1 deletion(-) create mode 100644 linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/bash/shared.sh create mode 100644 linux_os/guide/services/ssh/ssh_server/sshd_use_strong_macs/bash/shared.sh diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/bash/shared.sh b/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/bash/shared.sh new file mode 100644 index 0000000000..69c1f3eead --- /dev/null +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/bash/shared.sh @@ -0,0 +1,3 @@ +# platform = multi_platform_all + +{{{ bash_sshd_config_set(parameter="Ciphers", value="aes128-ctr,aes192-ctr,aes256-ctr,chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes128-ctr") }}} diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/oval/shared.xml b/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/oval/shared.xml index 3adae19c5a..0b20f775ce 100644 --- a/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/oval/shared.xml +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/oval/shared.xml @@ -1 +1 @@ -{{{ oval_sshd_config(parameter="Ciphers", value="((chacha20-poly1305@openssh\.com|aes256-gcm@openssh\.com|aes128-gcm@openssh\.com|aes256-ctr|aes128-ctr),?)") }}} +{{{ oval_sshd_config(parameter="Ciphers", value="((aes128-ctr|aes192-ctr|aes256-ctr|chacha20-poly1305@openssh\.com|aes256-gcm@openssh\.com|aes128-gcm@openssh\.com|aes256-ctr|aes128-ctr),?)") }}} diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_macs/bash/shared.sh b/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_macs/bash/shared.sh new file mode 100644 index 0000000000..f77be04a1b --- /dev/null +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_macs/bash/shared.sh @@ -0,0 +1,4 @@ +# platform = multi_platform_all + +{{{ bash_sshd_config_set(parameter="MACs", value="hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512,hmac-sha2-256,hmac-ripemd160") }}} + From 32c5bdbfc532d36bae5aaf0e0510b8516373598e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Mat=C4=9Bj=20T=C3=BD=C4=8D?= Date: Fri, 15 Nov 2019 14:44:25 +0100 Subject: [PATCH 2/2] Fixed sshd_use_strong_ciphers. - Fixed ciphers rule description metadata and bash remediation - removed duplicate ciphers. - Fixed ciphers rule OVAL. --- .../ssh/ssh_server/sshd_use_strong_ciphers/bash/shared.sh | 2 +- .../ssh/ssh_server/sshd_use_strong_ciphers/oval/shared.xml | 2 +- .../ssh/ssh_server/sshd_use_strong_ciphers/rule.yml | 3 +-- 7 files changed, 23 insertions(+), 4 deletions(-) diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/bash/shared.sh b/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/bash/shared.sh index 69c1f3eead..d30e534064 100644 --- a/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/bash/shared.sh +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/bash/shared.sh @@ -1,3 +1,3 @@ # platform = multi_platform_all -{{{ bash_sshd_config_set(parameter="Ciphers", value="aes128-ctr,aes192-ctr,aes256-ctr,chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes128-ctr") }}} +{{{ bash_sshd_config_set(parameter="Ciphers", value="aes128-ctr,aes192-ctr,aes256-ctr,chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com") }}} diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/oval/shared.xml b/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/oval/shared.xml index 0b20f775ce..474cb49979 100644 --- a/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/oval/shared.xml +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/oval/shared.xml @@ -1 +1 @@ -{{{ oval_sshd_config(parameter="Ciphers", value="((aes128-ctr|aes192-ctr|aes256-ctr|chacha20-poly1305@openssh\.com|aes256-gcm@openssh\.com|aes128-gcm@openssh\.com|aes256-ctr|aes128-ctr),?)") }}} +{{{ oval_sshd_config(parameter="Ciphers", value="((aes128-ctr|aes192-ctr|aes256-ctr|chacha20-poly1305@openssh\.com|aes256-gcm@openssh\.com|aes128-gcm@openssh\.com),?)+") }}} diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/rule.yml b/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/rule.yml index d4b61cedb9..90e11c0d99 100644 --- a/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/rule.yml +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_strong_ciphers/rule.yml @@ -9,8 +9,7 @@ description: |- Counter (CTR) mode is also preferred over cipher-block chaining (CBC) mode. The following line in /etc/ssh/sshd_config demonstrates use of those ciphers: -
Ciphers aes128-ctr,aes192-ctr,aes256-ctr
-
chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes128-ctr
+
Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr
The man page sshd_config(5) contains a list of supported ciphers. rationale: |-