Both of those files (as zip files) are clean.
The interesting thing here is that those download links are downloading files from server of freefr.dl.sourceforge.net and if you visit for example
you can see that in a way Sophos anti-virus is right and the freefr.dl.sourceforge.net server has (had) trojans in some files and obviously therefore Sophos blocks all files from that server...
In previous cases core developers of moodle.com have sent a report to most anti-virus software companies about false positives but this is a little different case - could you create a new issue to Moodle Tracker - http://tracker.moodle.org/secure/Dashboard.jspa - with some more details about the version of Sophos etc. (with a link to this post)
Note that you can install the latest versions also with GIT or CVS - see
or for example
(check different versions / branches and Downloads link...)