VPN i sig är ju inte speciellt "svår" att knäcka, om jag minns rätt så tog det inte mer än 4 timmar för en student att knäcka den krypteringen som heter "DC4".
Ska leta reda på där jag läste detta så ni får se det själva, jag hittar det inte just nu.
Återkommer...
EDIT:
Citat:
However, we also consider it our obligation to inform you about some of the negative aspects of PPTP VPN: While Microsoft claims that PPTP has a "good level of security that is suitable for most companies," security professionals such as Bruce Schneier think otherwise. A German student managed to crack PPTP passwords in 4 hours. Asleap by Joshua Wright has been extended to crack weak PPTP passwords. The authors of the premier Open Source PPTP implementations PPTPClient and Poptop recommend themselves against using PPTP. Others have found a flaw in Microsoft's PPTP implementation. Even Microsoft now admits that "as a VPN protocol, Microsoft considers PPTP to be non-strategic". Note also that PPTP is not an official Internet standard. It is a 'de-facto industry standard' set by Microsoft. In a nutshell, PPTP VPN can give you a false sense of security. Only use it, when you deal with non-sensitive data and when you need a VPN but have at the moment no possibility to install Open VPN. While PPTP VPN offers you immediate encryption and protection from the casual observer, always be aware that security experts and trained cryptographers can crack it with comparatively little effort.
Så gömmer sig tillräkligt många så kommer nog media maffian hävda deras rätt att "knäcka" detta med egna superdatorer, men det hoppas jag dröjer ett tag innan det inträffar, men man vet ju som sagt aldrig.
Källa:
https://www.perfect-privacy.com/faq.html#faq17