An attacker harvests identifying information about a victim via an active
session that the victim's browser has with a social networking site. A
victim may have the social networking site open in one tab or perhaps is
simply using the "remember me" feature to keep his or her session with the
social networking site active. An attacker induces a payload to execute in
the victim's browser that transparently to the victim initiates a request to
the social networking site (e.g., via available social network site APIs) to
retrieve identifying information about a victim. While some of this
information may be public, the attacker is able to harvest this information
in context and may use it for further attacks on the user (e.g., spear
phishing).
In one example of an attack, an attacker may post a malicious posting that
contains an image with an embedded link. The link actually requests
identifying information from the social networking site. A victim who views
the malicious posting in his or her browser will have sent idenditifying
information to the attacker, as long as the victim had an active session
with the social networking site. There are many other ways in which the
attacker may get the payload to execute in the victim's browser mainly by
finding a way to hide it in some reputable site that the victim visits. The
attacker could also send the link to the victim in an e-mail and trick the
victim into clicking on the link.
This attack is basically a cross site request forgery attack with two main
differences. First, there is no action that is performed on behalf of the
user aside from harvesting information. So standard CSRF protection may not
work in this situation. Second, what is important in this attack pattern is
the nature of the data being harvested, which is identifying information
that can be obtained and used in context. This real time harvesting of
identifying information can be used as a prelude for launching real time
targetted social engineering attacks on the victim.
Attack Prerequisites
The victim has an active session with the social networking site.
Attacker Skills or Knowledge Required
Skill or Knowledge Level: High
An attacker should be able to create a payload and deliver it to the
victim's browser.
Skill or Knowledge Level: Medium
An attacker needs to know how to interact with various social
networking sites (e.g., via available APIs) to request information and
how to send the harvested data back to the attacker.
Solutions and Mitigations
Usage: Users should always explicitly log out from the social networking
sites when done using them.
Usage: Users should not open other tabs in the browser when using a social
networking site.
Description
