More often than not, there is one person who generates the original "fake" for the same kind of reasons people create & spread viruses. EG (brief) notoriety, practical joke, personal vendetta/axe to grind.
Then there are many more innocent (although perhaps careless/selfish) people who propagate the file, more intent on bringing it quickly to the attention of whatever forum they inhabit, than on actually testing or verifying it themselves. They may simply be motivated by a desire to have others test and take the risk first, or to enjoy the "honour" of being first to post, should it turn out to be genuine (some are, occasionally).
But there are also other possibilities. Frequent rumour has it that several of the over-enthusiastically posted fake conax files are posted by satellite dealers in an attempt to boost conax CAM sales.
There is no question that CAM prices are adjusted when a hack becomes public. The very day that the Viaccess hack went public (12 feb 01) Viaccess CI CAM prices increased by 25%...
It is also true that many of the most frequent posters in satellite boards are actually proprietors or employees of such companies. Many of the sites hosting boards are funded directly or indirectly by satellite dealerships.
There have also been instances of malicious posting of files that will actually damage your equipment. Maybe you recall an early AllCAM (v0.04.60se, 10-march-00) firmware for the series-1 Irdeto CAM. It had a feature built-in that disabled the CAM after a certain number of uses, damaging the loader and so rendering it not just unusable ("licence error") but also non-patchable. Why would anyone do that? Who knows. Either the "virus" mentality mentioned above, or maybe something more sinister. I can imagine, for example, that Mindport (owners of Irdeto) might have something to gain from circulating a file that knocked out reverse-engineered CAMs (stranger things have happened ... see the breaking Canal+ vs NDS saga...).
And a very similar thing happened again with the first Alphacrypt firmware for the newer Euro CAM.
When you swim with sharks, expect to get bitten...
2old