The American band's latest single 'Payphone' featuring Wiz Khalifa is not released in the UK until June 17, but appears to be on very high demand ahead of its release.
A cover by a collective named Precision Tunes has reached as high as number five in the iTunes chart today (June 14), while the original remains unreleased.
This version had reached number 14 in the official chart update on Wednesday (June 13).
The practice of unofficial cover versions often occurs when an upcoming song has received lots of airplay but has yet to be released.
However, the original artist's record company normally spots the high chart placing and rush releases the track, which shoots the original high up the downloads chart, and sends the cover version out.
Maroon 5 have yet to rush release their original version, making it highly likely that the Precision Tunes cover will reach the top ten on Sunday.
Precision Tunes have recorded a large number of covers in the past, including songs originally by Chris Brown, Usher and Justin Bieber.
A cover of Flo Rida's 'Whistle' by a group named Can You Blow My reached number 38 last week, forcing the original to be rush-released halfway through the week.
The method is somewhat similar to the Top of the Pops record series by Pickwick Records from 1968-1985, which released compilations of similar-sounding cover versions in the years before collections such as the Now! series were created.
Watch the video for Maroon 5's 'Payphone' below: