The operating system must implement cryptography to protect the integrity of remote access sessions.

From Apple OS X 10.9 (Mavericks) Workstation Security Technical Implementation Guide

Associated with: CCI-001453

SV-72691r1_rule The operating system must implement cryptography to protect the integrity of remote access sessions.

Vulnerability discussion

The telnet service must be disabled, as it sends all data, including the user's password, in a clear text form that can be easily intercepted and read. Passwords need to be protected at all times and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily compromised. Disabling telnet is one way to mitigate this risk. Authorized users should be instructed to use an alternate service that implements cryptography for remote access sessions, such as SSH.

Check content

The service 'telnet' should be disabled, to check the status of the service, run the following command: sudo /usr/libexec/PlistBuddy -c 'print com.apple.telnetd:Disabled' /var/db/launchd.db/com.apple.launchd/overrides.plist If the returned value isn't 'true' or doesn't exist, this is a finding.

Fix text

To set the telnet service to disabled, run the following command: sudo defaults write /private/var/db/launchd.db/com.apple.launchd/overrides.plist 'com.apple.telnetd' -dict Disabled -bool true

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