I am new to Ubuntu server. I found this post about a vulnerability in Debian's APT. Do you think this issue has been resolved?
On January 22nd, Max Justicz published a write up detailing a vulnerability in the apt client. Using Man in the Middle techniques, an attacker can intercept the apt communication while it downloads a software package, replace the requested package content with their own binary, and execute it with root privileges.
I found a vulnerability in apt that allows a network man-in-the-middle (or a malicious package mirror) to execute arbitrary code as root on a machine installing any package. The bug has been fixed in the latest versions of apt. If you’re worried about being exploited during the update process, you can protect yourself by disabling HTTP redirects while you update.