The .shtml extension enabled SSI. This was a revelation. Suddenly, you could do things that felt like magic.
If a guestbook form does not properly sanitize user inputs, an attacker can input an SSI directive instead of a standard text comment. guestbook shtml
Let’s crack open the digital time capsule and talk about why the guestbook.shtml file was the unsung hero of the early web. guestbook shtml
Attackers gain a shell equivalent, enabling them to execute administrative system commands. guestbook shtml
The .shtml guestbook came with a specific aesthetic that we rarely see today.
#guestbook-form { width: 500px; margin: auto; }