SSH enables encrypted remote access and administration, but weak credentials, exposed services, and misconfiguration can permit unauthorized access.
Search across headline titles and summaries.
Background for this topic.
SSH (Secure Shell) is a protocol for establishing a cryptographically protected connection to a remote computer. It supports interactive administration, command execution, file transfer, and related services such as port forwarding. SSH provides confidentiality and integrity for the session, while host keys help the client verify that it is connecting to the intended server.
Security depends on how SSH is deployed and how its credentials are managed. An internet-exposed service may attract password guessing, and vulnerable SSH implementations can provide an entry point; a stolen private key or an overly permissive authorized_keys entry may enable unauthorized access. Useful controls include timely patching, restricting network exposure, disabling password authentication where practical, protecting keys with strong passphrases or hardware-backed storage, limiting account privileges, and reviewing authentication logs. Administrators should verify host keys to reduce man-in-the-middle risk and promptly remove or rotate credentials during personnel changes or suspected compromise.
Almost 11 million internet-exposed SSH servers are vulnerable to the Terrapin attack that threatens the integrity of some SSH connections. [...]
Security researchers from Ruhr University Bochum have discovered a vulnerability in the Secure Shell (SSH) cryptographic network protocol that could allow an attacker to downgrade the connection's security by breaking the integrity of the secure channel