Configure a Proper SSH Service Authentication Mode

A proper authentication mode helps ensure user and system data security. Typically, the user/password authentication mode is suitable for human-machine users. In non-interactive login scenarios, the public and private keys are suitable for authentication. In high-risk scenarios, only the public a...

Enable PAM Authentication

Pluggable Authentication Modules PAM on the Linux platform provides a series of open source shared library files .so files. You can flexibly control the authentication process by configuring parameters. After PAM authentication is configured for SSH, the user authentication management module of t...

Configure a Proper Number of Concurrent Sessions Allowed for a Single SSH Connection

SSH allows a client that supports multiplexing to establish multiple sessions based on a network connection. MaxSessions limits the number of concurrent SSH sessions that can be established for each network connection. This prevents system resources from being occupied by a single connection or a...

CVE-2025-47203

dbclient in Dropbear SSH before 2025.88 allows command injection via an untrusted hostname argument, because a shell is used...

Disable PermitUserEnvironment

PermitUserEnvironment allows users to set SSH environment variables, which may be exploited by attackers to launch attacks. If PermitUserEnvironment is set to yes, attackers can modify SSH environment variables to evade the security mechanism or execute attack code. This configuration must be...

Do Not Preset authorized_keys for the SSH Service

authorizedkeys specifies the public key of the remote host. You can store the public key in the $HOME/.ssh/authorizedkeys file in the home directory for public key authentication. Then you can directly log in to the system. If authorizedkeys is preset in the system and public and private key...

Bind Network Interfaces to the Correct Zones

Different filtering policies can be configured for different firewall zones. If the server network is complex and has multiple interfaces that provide different service functions, it is recommended that interfaces be configured in different zones and different firewall policies be configured. For...

Configure Proper SSH Key Exchange Algorithms

Key exchange is a process in which two parties exchange keys to allow the use of an encryption algorithm. A secure key exchange algorithm enables them to securely exchange keys, thereby using encryption algorithms to encrypt messages to be sent and decrypt received messages. Set the SSH key...

CVE-2025-4041

In Optigo Networks ONS NC600 versions 4.2.1-084 through 4.7.2-330, an attacker could connect with the device's ssh server and utilize the system's components to perform OS command executions...

CVE-2025-4041 Use of Hard-coded Credentials Optigo Networks ONS NC600

In Optigo Networks ONS NC600 versions 4.2.1-084 through 4.7.2-330, an attacker could connect with the device's ssh server and utilize the system's components to perform OS command executions...

CVE-2025-4041

Optigo Networks ONS NC600, versions 4.2.1-084 through 4.7.2-330, are affected by CVE-2025-4041. An attacker who can access the device’s SSH service could leverage system components to execute OS commands on the device. The impact is consistent with a remote command execution risk affecting availa...

CVE-2025-4041 Use of Hard-coded Credentials Optigo Networks ONS NC600

In Optigo Networks ONS NC600 versions 4.2.1-084 through 4.7.2-330, an attacker could connect with the device's ssh server and utilize the system's components to perform OS command executions...

PT-2025-19913 · Optigo Networks · Optigo Networks Ons Nc600

Name of the Vulnerable Software and Affected Versions: Optigo Networks ONS NC600 versions 4.2.1-084 through 4.7.2-330 Description: An issue exists where an attacker could connect to the device's ssh server and utilize the system's components to perform OS command executions. Recommendations: For...

ROS-20250505-01

The vulnerability in the Golang programming language SSH server is related to the fact that the application does not control internal resources consumption in the ssh packet when working with clients that are slow or do not perform key exchange at all. or do not perform key exchange at all...

GO-2025-3649 Fleet doesn’t validate a server’s certificate when connecting through SSH in github.com/rancher/fleet

Fleet doesn’t validate a server’s certificate when connecting through SSH in github.com/rancher/fleet...

golang.org/x/crypto/ssh: Misuse of ServerConfig.PublicKeyCallback may cause authorization bypass in golang.org/x/crypto

A flaw was found in the x/crypto/ssh go library. Applications and libraries that misuse the ServerConfig.PublicKeyCallback callback may be susceptible to an authorization bypass. For example, an attacker may send public keys A and B and authenticate with A. PublicKeyCallback would be called only...

Exploit for Missing Authentication for Critical Function in Erlang Erlang\/Otp

✅ Result The server responded to an SSH message ID 80 0x5...

📄 Erlang-Based SSH OTP Pre-Authentication Remote Code Execution

This Metasploit module detect and exploits CVE-2025-32433, a pre-authentication vulnerability in Erlang-based SSH servers that allows remote command execution. By sending crafted SSH packets, it executes a payload to establish a reverse shell on the target system. The exploit leverages a flaw in...

Man-In-The-Middle (MITM)

github.com/rancher/flee is vulnerable to Man-in-the-Middle MitM attack. The vulnerability is due to improper certificate validation and Fleet automatically trusting remote server SSH certificates if not listed in the knownhosts file, allowing potential spoofing by an attacker...

ROS-20250430-05

Vulnerability of Erlang programming language OTP library set is related to improper packet handling SFTP. Exploitation of the vulnerability could allow an attacker acting remotely to cause a denial of service. denial of service Vulnerability of SSH protocol implementation from Erlang/OTP library...