SSH vulnerabilities: HMAC algorithms and CBC ciphers
Issue
- the following vulnerabilities were received on RHEL 5 and RHEL 6 servers (related to RHEL7 too):
SSH Insecure HMAC Algorithms Enabled
SSH CBC Mode Ciphers Enabled
Below is the update from a security scanner regarding the vulnerabilities
Vulnerability Name: SSH Insecure HMAC Algorithms Enabled
Description: Insecure HMAC Algorithms are enabled
Solution:
Disable any 96-bit HMAC Algorithms.Disable any MD5-based HMAC Algorithms.
Vulnerability Name: SSH CBC Mode Ciphers Enabled
Description: CBC Mode Ciphers are enabled on the SSH Server.
Solution: Disable CBC Mode Ciphers and use CTR Mode Ciphers
Environment
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 6
-
Red Hat Enterprise Linux 5
-
OpenSSH
- Putty
Subscriber exclusive content
A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more.