Cryptography / SSH Server CBC Mode Ciphers Enabled

Description

SSH Server CBC Mode Ciphers Enabled is a vulnerability that affects security in the domain of Cryptography. It is classified as CWE-327, which is defined as the use of cryptographic algorithms that rely on the Cipher Block Chaining (CBC) Mode encryption. This vulnerability can be discovered through various means, such as the use of automated vulnerability assessment tools, manual source code review, or by inspecting the configurations of the SSH server. According to the OWASP Testing Guide, the CBC Mode Ciphers Enabled vulnerability can be exploited by sending specially crafted packets to the server, which can potentially allow attackers to gain unauthorized access to the server.

Risk

The risk that this vulnerability can pose is high due to its ability to provide attackers with unauthorized access to the server. This can potentially lead to the attacker gaining access to confidential information, as well as gaining control over the server itself. The consequences of an attack depending on the severity of the exploitation can range from a minor data leak to a full-scale breach of the server.

Solution

The best solution to remediate this vulnerability is to disable CBC Mode Ciphers from the SSH server. This can be done by using the command “Ciphers Disable CBC”. Additionally, it is recommended to use the newer and more secure ciphers such as AES-CTR and AES-GCM.