"Vermin Mangle" is a song by English rock band Cardiacs. The song was written by Tim Smith, who played it live during solo performances in 2000 and 2006, and was supposed to be the final track of the album LSD which was left unfinished after Smith had a heart attack in 2008. Following Smith's death, it was released as a free download on 1 September 2020 through the band's Bandcamp page as the second single from the album, to mark his funeral that same day. Intended as a thank you to the group's fans, the song features the circus, progressive rock and psychedelic instrumentation that drove much of the band's work.