[[!meta date="Thu Jul 24 21:15:00 2014"]]
[[!meta title="Security hole in I2P 0.9.13"]]

[[!tag security/fixed]]

A security hole affects I2P 0.9.13, that is part of Tails 1.1
and earlier.

Scope and severity
==================

If you are [[using I2P|doc/anonymous_internet/i2p]] in Tails 1.1 and
earlier, an attacker can de-anonymize you: they can learn the IP
address that identifies you on the Internet.

To be able to conduct this attack:

1. the attacker must be able to affect the content of a website that
   you are visiting using the [[Tor
   Browser|doc/anonymous_internet/Tor_Browser]] in Tails — many people
   are able to do so;

2. and, the attacker must find out how to exploit this security hole;
   this information has not been published yet, but they may somehow
   already have discovered it, or been made aware of it.

<div class="note">

<p><strong>Tails does not start I2P by default.</strong> [[This design
decision|contribute/design/I2P#design]] was made precisely in order to
protect the Tails users who do not use I2P from security holes in this
piece of software.</p>

<p>Still, an attacker who would also be able to start I2P on your
Tails, either by exploiting another undisclosed security hole, or by
tricking you into starting it yourself, could then use this I2P
security hole to de-anonymize you.</p>

</div>

Temporary solutions
===================

You can protect yourself from this security hole until it
is corrected.

Do not start I2P in Tails 1.1 and earlier. You can protect yourself
further by removing the `i2p` package every time you start Tails:

1. [[Set an administration
   password|doc/first_steps/startup_options/administration_password]].
1. Run this command in a <span class="application">Root
   Terminal</span>:

       apt-get purge i2p

However, if you really need to use I2P in Tails 1.1: before you start
I2P, disable JavaScript globally [[with
NoScript|doc/anonymous_internet/Tor_Browser#noscript]] in the
Tor Browser.

Credits
=======

This security hole was reported to us by Exodus Intelligence.
