ubiquity-slideshow-ubuntu before 58.2, during installation, allows remote man-in-the-middle attackers to execute arbitrary web script or HTML and read arbitrary files via a crafted attribute in the <a> tag of a Twitter feed.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2012-0979
https://bugs.launchpad.net/ubuntu/%2Bsource/ubiquity-slideshow-ubuntu/%2Bbug/991982