Secunia

Some vulnerabilities have been discovered in chetcpasswd, which can be exploited by malicious people to bypass security restrictions, identify valid user accounts and potentially compromise vulnerable systems.

1) Input passed in the "X-Forwarded-For" HTTP header is trusted from all clients. This can be exploited to bypass IP address checks by connecting to chetcpasswd and passing arbitrary values in the header.

2) Different error messages are returned depending on whether an unsuccessful password change attempt is performed with a valid or invalid username.

3) Boundary errors exist within the "main()" function in chetcpasswd.c. This can be exploited to cause a heap-based buffer overflow by passing long "X-Forwarded-For" HTTP headers or running the program locally with long values in the "REMOTE_ADDR" environment variable.

Successful exploitation potentially allows for execution of arbitrary code as the root user. It doesn't require passing the IP address check, as the buffer overflow takes place before it.

It has also been reported that the product does not introduce delays after failed password change attempts, making dictionary attacks easier to perform.

The vulnerabilities are confirmed in version 2.3.3. Other versions may also be affected.

Solution
Update to version 2.4, which fixes vulnerability #1 and #3.
Further details available in Customer Area

Provided and/or discovered by
1+2) Bas Zoetekouw
3) João Eriberto Mota Filho

Changelog
Further details available in Customer Area

Original Advisory
1+2) http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=394454

Other references
Further details available in Customer Area

Deep Links
Links available in Customer Area