306 research outputs found
Synesthesia: Detecting Screen Content via Remote Acoustic Side Channels
We show that subtle acoustic noises emanating from within computer screens
can be used to detect the content displayed on the screens. This sound can be
picked up by ordinary microphones built into webcams or screens, and is
inadvertently transmitted to other parties, e.g., during a videoconference call
or archived recordings. It can also be recorded by a smartphone or "smart
speaker" placed on a desk next to the screen, or from as far as 10 meters away
using a parabolic microphone.
Empirically demonstrating various attack scenarios, we show how this channel
can be used for real-time detection of on-screen text, or users' input into
on-screen virtual keyboards. We also demonstrate how an attacker can analyze
the audio received during video call (e.g., on Google Hangout) to infer whether
the other side is browsing the web in lieu of watching the video call, and
which web site is displayed on their screen
PILOT: Password and PIN Information Leakage from Obfuscated Typing Videos
This paper studies leakage of user passwords and PINs based on observations
of typing feedback on screens or from projectors in the form of masked
characters that indicate keystrokes. To this end, we developed an attack called
Password and Pin Information Leakage from Obfuscated Typing Videos (PILOT). Our
attack extracts inter-keystroke timing information from videos of password
masking characters displayed when users type their password on a computer, or
their PIN at an ATM. We conducted several experiments in various attack
scenarios. Results indicate that, while in some cases leakage is minor, it is
quite substantial in others. By leveraging inter-keystroke timings, PILOT
recovers 8-character alphanumeric passwords in as little as 19 attempts. When
guessing PINs, PILOT significantly improved on both random guessing and the
attack strategy adopted in our prior work [4]. In particular, we were able to
guess about 3% of the PINs within 10 attempts. This corresponds to a 26-fold
improvement compared to random guessing. Our results strongly indicate that
secure password masking GUIs must consider the information leakage identified
in this paper
xLED: Covert Data Exfiltration from Air-Gapped Networks via Router LEDs
In this paper we show how attackers can covertly leak data (e.g., encryption
keys, passwords and files) from highly secure or air-gapped networks via the
row of status LEDs that exists in networking equipment such as LAN switches and
routers. Although it is known that some network equipment emanates optical
signals correlated with the information being processed by the device
('side-channel'), intentionally controlling the status LEDs to carry any type
of data ('covert-channel') has never studied before. A malicious code is
executed on the LAN switch or router, allowing full control of the status LEDs.
Sensitive data can be encoded and modulated over the blinking of the LEDs. The
generated signals can then be recorded by various types of remote cameras and
optical sensors. We provide the technical background on the internal
architecture of switches and routers (at both the hardware and software level)
which enables this type of attack. We also present amplitude and frequency
based modulation and encoding schemas, along with a simple transmission
protocol. We implement a prototype of an exfiltration malware and discuss its
design and implementation. We evaluate this method with a few routers and
different types of LEDs. In addition, we tested various receivers including
remote cameras, security cameras, smartphone cameras, and optical sensors, and
also discuss different detection and prevention countermeasures. Our experiment
shows that sensitive data can be covertly leaked via the status LEDs of
switches and routers at a bit rates of 10 bit/sec to more than 1Kbit/sec per
LED
POWER-SUPPLaY: Leaking Data from Air-Gapped Systems by Turning the Power-Supplies Into Speakers
It is known that attackers can exfiltrate data from air-gapped computers
through their speakers via sonic and ultrasonic waves. To eliminate the threat
of such acoustic covert channels in sensitive systems, audio hardware can be
disabled and the use of loudspeakers can be strictly forbidden. Such audio-less
systems are considered to be \textit{audio-gapped}, and hence immune to
acoustic covert channels.
In this paper, we introduce a technique that enable attackers leak data
acoustically from air-gapped and audio-gapped systems. Our developed malware
can exploit the computer power supply unit (PSU) to play sounds and use it as
an out-of-band, secondary speaker with limited capabilities. The malicious code
manipulates the internal \textit{switching frequency} of the power supply and
hence controls the sound waveforms generated from its capacitors and
transformers. Our technique enables producing audio tones in a frequency band
of 0-24khz and playing audio streams (e.g., WAV) from a computer power supply
without the need for audio hardware or speakers. Binary data (files,
keylogging, encryption keys, etc.) can be modulated over the acoustic signals
and sent to a nearby receiver (e.g., smartphone). We show that our technique
works with various types of systems: PC workstations and servers, as well as
embedded systems and IoT devices that have no audio hardware at all. We provide
technical background and discuss implementation details such as signal
generation and data modulation. We show that the POWER-SUPPLaY code can operate
from an ordinary user-mode process and doesn't need any hardware access or
special privileges. Our evaluation shows that using POWER-SUPPLaY, sensitive
data can be exfiltrated from air-gapped and audio-gapped systems from a
distance of five meters away at a maximal bit rates of 50 bit/sec
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