Title

The SSH daemon must not allow compression or must only allow compression after successful authentication. (Cat II impact)

Discussion

If compression is allowed in an SSH connection prior to authentication, vulnerabilities in the compression software could result in compromise of the system from an unauthenticated connection, potentially with root privileges.

Check Content

Fix Text

Edit the SSH daemon configuration and add or edit the Compression setting value to no or delayed.

Additional Identifiers

Rule ID: SV-26787r1_rule

Vulnerability ID: V-22488

Group Title: GEN005539

Expert Comments

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