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Age in Days
CVSS Score
Patch within next
Risk Level

6976


5.0

180 Days

None

 

This vulnerability is 19 years 1 months and 5 days old and there are presently no exploits available for the it. The vulnerability itself is over a year old, and while there are presently no publicly known exploits available for it, the vulnerability should be patched within the next three months.

 

Synopsis

A Telnet server is listening on the remote port.

 

Vulnerability Description

The remote host is running a Telnet server, a remote terminal server. Telnet's simplicity is its greatest strength and its greatest weakness. One of the biggest problems with telnet is that whatever text you type in is sent across the network essentially unchanged. This is a problem primarily because people typically need to log into the remote computer in order to use it with telnet.

That means that their user name and password are both sent across the network in plain text. Remembering the way the internet works, that means that the way the user name and password get from your computer all the way to the computer you're logging into is analogous to writing it on a postcard and passing it to someone who shouts the address and contents of the packet across a crowded room to someone else who writes it down on another postcard and hands it to someone else to repeat the procedure enough times until a postcard with that information on it is handed to the person (or computer) you were sending your user name and password to. The reason this is bad is that you may not trust all the people or computers in between, who may happen to be in that chain of postcard-passing or who may simply be in the room when your postcard is shouted out. If those computers or people felt like it, they could also write down your user name and password somewhere else, and save it for a later date. They can then log into the same computer you logged into, pretending to be you.

 

Solution

Part of the problem of the telnet protocol is that many people don't know that there are alternatives that are better suited for the job than the original telnet is. There is a protocol called SSH (which stands for Secure SHell), for example, that provides the same basic capabilities that telnet does—that is, it provides a command-line interface to a remote computer in a virtually identical way—with one main difference: all text that is sent back and forth is encrypted in a way that only the two computers involved in the conversation can understand. That way passwords, user names, and other sensitive information can be safely written on a postcard, handed to another computer, and even shouted across the room, without fear that anyone who reads the postcard or hears it shouted across the room could possibly understand what it means. In virtually every instance, SSH is a drop-in, secure replacement for telnet. SSH also has additional features that telnet does not have that make it even better—for example, it can compress traffic between two computers so it needs less space (or bandwidth) than telnet would need to say the same thing in plain text (SSH can also be used for secure file transfer and connection tunnelling).

There are many programs that implement the SSH protocol. Some of the best ones are free, and available here.

 

Further Information

There is no further information available at this time.

 

CVE References

N/A NIST | MITRE | CVEDetails

 

Get in touch

Should you have any questions regarding this or any security matter, please do not hesitate to get in touch by emailing the Hedgehog Cyber Operations Team.

Whilst every effort is made to ensure the accuracy and robustness of any information presented, it is not possible for Hedgehog Cyber to test every possible scenario an organisation may face, and Hedgehog Cyber cannot be held liable for any loss or damage which may arise from taking action on any of the contents provided. Hedgehog Cyber strongly advises that all recommendations, solutions and detection methods detailed, are thoroughly reviewed and tested in non-production environments before being considered suitable for production release, in-line with any existing internal change control procedures.