CVE-2018-12551

When Eclipse Mosquitto version 1.0 to 1.5.5 (inclusive) is configured to
use a password file for authentication, any malformed data in the password
file will be treated as valid. This typically means that the malformed data
becomes a username and no password. If this occurs, clients can circumvent
authentication and get access to the broker by using the malformed
username. In particular, a blank line will be treated as a valid empty
username. Other security measures are unaffected. Users who have only used
the mosquitto_passwd utility to create and modify their password files are
unaffected by this vulnerability.

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