[Bglug] GRUB2 security flaw

Brad Rodriguez brad at bradrodriguez.com
Fri Dec 18 12:40:34 EST 2015

Note that this requires physical access to the machine, so it's a local
exploit only.


"The researchers, Hector Marco and Ismael Ripoll from the Cybersecurity
Group at Polytechnic University of Valencia, found that it’s possible to
bypass all security of a locked-down Linux machine by exploiting a bug
in the Grub2 bootloader. Essentially, hitting backspace 28 times when
the machine asks for your username accesses the “Grub rescue shell,” and
once there, you can access the computer’s data or install malware.
Fortunately, Marco and Ripoll have made an emergency patch to fix the
Grub2 vulnerability. Ubuntu, Red Hat, and Debian have all issued patches
to fix it as well."

For the gory details:

brad at bradrodriguez.com

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