Editing DeCSS (section)

== Technology and derived works ==
{{See also|libdvdcss}}
When the release of the DeCSS source code made the CSS algorithm available for public scrutiny, it was soon found to be susceptible to a [[brute-force attack]] quite different from DeCSS. The encryption is only [[40-bit encryption|40-bit]], and does not use all keys; a high-end home computer in 1999 running optimized code could brute-force it within 24 hours, and modern computers can brute-force it in a few seconds or less.<ref>{{Cite web|url=https://www.cs.cmu.edu/~dst/DeCSS/Kesden/index.html|title=Content Scrambling System (CSS): Introduction|website=www.cs.cmu.edu|access-date=29 August 2019|archive-date=1 July 2024|archive-url=https://web.archive.org/web/20240701185436/https://www.cs.cmu.edu/~dst/DeCSS/Kesden/index.html|url-status=live}}</ref>

Programmers around the world created hundreds of programs equivalent to DeCSS, some merely to demonstrate the trivial ease with which the system could be bypassed, and others to add DVD support to [[Open-source license|open source]] movie players. The licensing restrictions on CSS make it impossible to create an open source implementation through official channels, and closed source drivers are unavailable for some operating systems, so some users need DeCSS or a similar tool to watch even legally obtained movies.