InterAccess TelnetD Server 4.0 Buffer Overflow Vulnerability

Bugtraq ID:	995
Class:	Boundary Condition Error
CVE:
Remote:	Yes
Local:	Yes
Published:	Feb 21 2000 12:00AM
Updated:	Feb 21 2000 12:00AM
Credit:	Posted to Bugtraq on February 21, 2000 by USSR Labs <[email protected]>.
Vulnerable:	Pragma Systems InterAccess TelnetD Server 4.0 Build 4 - Microsoft Windows NT 4.0
Not Vulnerable:	Pragma Systems InterAccess TelnetD Server 4.0 Build 7 - Microsoft Windows NT 4.0

InterAccess TelnetD Server 4.0 Buffer Overflow Vulnerability

The Pragma Systems InterAccess TelnetID Server 4.0 (Build 4) has an unchecked buffer in the code that handles login commands. Arbitrary code is capable of being executed on the InterAccess TelnetD Server if a string of over 300 characters is used as a login name.

InterAccess TelnetD Server 4.0 Buffer Overflow Vulnerability

USSR Labs Exploit:
Executable - ex_telnd.exe
Source - ex_telnd.zip

This exploit triggers a server crash by consuming 100% of the CPU cycles.

• /data/vulnerabilities/exploits/ex_telnd.exe
• /data/vulnerabilities/exploits/ex_telnd.zip

InterAccess TelnetD Server 4.0 Buffer Overflow Vulnerability

Solution:
Pragma Systems has released a new version of InterAccess TelnetD Server, Build 8, which rectifies this issue. It is available for download at the following website:

http://www.pragmasys.com/TelnetD/

InterAccess TelnetD Server 4.0 Buffer Overflow Vulnerability

References:

• Pragma Systems Response (Pragma Systems)