Earlier this year, it was revealed that previously unheard Kurt Cobain music would be featured in the upcoming HBO documentary Kurt Cobain: Montage of Heck. Thanks to director Brett Morgen, we now know the film's soundtrack will feature a "mind blowing 12 minute acoustic Cobain unheard track."

Anticipation just keeps on building for Kurt Cobain: Montage of Heck, which will premiere May 4 on HBO. Kurt Cobain's daughter, Frances Bean Cobain, even served as executive producer of the film.

The deeply personal look into Kurt Cobain's life has been praised by various reviewers, who caught a special screening of the film at this year's Sundance Film Festival. Not much is known about the never-before-heard music that will be released along with the film, though Brett Morgen offered some exciting information on one track.

In other Nirvana news, an unreleased track from the band was supposedly uploaded onto YouTube by a self-described hacker. The uploader claimed "Flacid Bone," which was scrapped by Nirvana because Kurt Cobain hated the song, was stolen from Courtney Love.

According to TMZ, Courtney Love and an unnamed former Nirvana member confirmed "Flacid Bone" was a fake. Additionally, Love is working with law enforcement to track down the individual who uploaded the phony Nirvana track onto YouTube.

Be sure to tune in to HBO on May 4 for the television premiere of Kurt Cobain: Montage of Heck.

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