Sven Dreyer discovered that KPhone, a Voice over IP client for KDE, creates a configuration file world-readable, which could leak sensitive information like SIP passwords.
The old stable distribution (woody) doesn't contain kphone packages.
For the stable distribution (sarge) this problem has been fixed in version 4.1.0-2sarge1.
For the unstable distribution (sid) this problem has been fixed in version 4.2-6.
We recommend that you upgrade your kphone package. If your current kphonerc has too lax permissions, you'll need to reset them manually.