The latexcgi service currently running at texlive.net is an open source service with code available at GitHub.
The server accepts HTTP POST submissions and returns results (typically PDF but also potential plain text log files or HTML).
No information supplied is stored long term:
Any documents submitted are saved to a temporary directory which is deleted as soon as the request is processed (typically a few seconds after submission).
Resulting PDF documents or log files are returned to the user with a public but obfuscated URL.
This document will be served for between 1 and 2 hours. A scheduled job runs every hour deleting any documents that are more than an hour old.
In common with most web servers basic logging information is recorded by the server, which include the IP address of the machine making the document request and other information. The default apache web server logging is used here which just preserves this information for two weeks, for debugging information. These log files may be used for basic reporting of, for example, basic usage counts on the server, but no personal information is extracted.
The site only processes POST requests to the latexcgi script and does not use cookies or any other individual data. Note however that sites making use of this service may have user login or other personal data stored in cookies. Any such data is not controlled (or passed to) this site.
David Carlisle