Cisco ONS15454 and ONS15327 running ONS before 3.4 have an account for the VxWorks Operating System in the TCC, TCC+ and XTC that cannot be changed or disabled, which allows remote attackers to gain privileges by connecting to the account via Telnet.

Cisco ONS15454 and ONS15327 running ONS before 3.4 stores usernames and passwords in cleartext in the image database for the TCC, TCC+ or XTC, which could allow attackers to gain privileges by obtaining the passwords from the image database or a backup.

Cisco ONS15454 and ONS15327 running ONS before 3.4 allows remote attackers to modify the system configuration and delete files by establishing an FTP connection to the TCC, TCC+ or XTC using a username and password that does not exist.

Cisco ONS15454 and ONS15327 running ONS before 3.4 uses a "public" SNMP community string that cannot be changed, which allows remote attackers to obtain sensitive information.

Cisco ONS15454 and ONS15327 running ONS before 3.4 allows attackers to cause a denial of service (reset) via an HTTP request to the TCC, TCC+ or XTC, in which the request contains an invalid CORBA Interoperable Object Reference (IOR).

Cisco ONS15454 and ONS15327 running ONS before 3.4 allows attackers to cause a denial of service (reset to TCC, TCC+, TCCi or XTC) via a malformed HTTP request that does not contain a leading / (slash) character.