#covertchannels — Public Fediverse posts

J. Vilalonga et al., "TorKameleon: Improving Tor's Censorship Resistance With K-anonimization and Media-based Covert Channels"¹

The use of anonymity networks such as Tor and similar tools can greatly enhance the privacy and anonymity of online communications. Tor, in particular, is currently the most widely used system for ensuring anonymity on the Internet. However, recent research has shown that Tor is vulnerable to correlation attacks carried out by state-level adversaries or colluding Internet censors. Therefore, new and more effective solutions emerged to protect online anonymity. Promising results have been achieved by implementing covert channels based on media traffic in modern anonymization systems, which have proven to be a reliable and practical approach to defend against powerful traffic correlation attacks. In this paper, we present TorKameleon, a censorship evasion solution that better protects Tor users from powerful traffic correlation attacks carried out by state-level adversaries. TorKameleon can be used either as a fully integrated Tor pluggable transport or as a standalone anonymization system that uses K-anonymization and encapsulation of user traffic in covert media channels. Our main goal is to protect users from machine and deep learning correlation attacks on anonymization networks like Tor. We have developed the TorKameleon prototype and performed extensive validations to verify the accuracy and experimental performance of the proposed solution in the Tor environment, including state-of-the-art active correlation attacks. As far as we know, we are the first to develop and study a system that uses both anonymization mechanisms described above against active correlation attacks.

#arXiv #ResearchPapers #TorKameleon #Tor #CensorshipResistance #Privacy #CovertChannels
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¹ https://arxiv.org/abs/2303.17544

J. Vilalonga et al., "TorKameleon: Improving Tor's Censorship Resistance With K-anonimization and Media-based Covert Channels"¹

The use of anonymity networks such as Tor and similar tools can greatly enhance the privacy and anonymity of online communications. Tor, in particular, is currently the most widely used system for ensuring anonymity on the Internet. However, recent research has shown that Tor is vulnerable to correlation attacks carried out by state-level adversaries or colluding Internet censors. Therefore, new and more effective solutions emerged to protect online anonymity. Promising results have been achieved by implementing covert channels based on media traffic in modern anonymization systems, which have proven to be a reliable and practical approach to defend against powerful traffic correlation attacks. In this paper, we present TorKameleon, a censorship evasion solution that better protects Tor users from powerful traffic correlation attacks carried out by state-level adversaries. TorKameleon can be used either as a fully integrated Tor pluggable transport or as a standalone anonymization system that uses K-anonymization and encapsulation of user traffic in covert media channels. Our main goal is to protect users from machine and deep learning correlation attacks on anonymization networks like Tor. We have developed the TorKameleon prototype and performed extensive validations to verify the accuracy and experimental performance of the proposed solution in the Tor environment, including state-of-the-art active correlation attacks. As far as we know, we are the first to develop and study a system that uses both anonymization mechanisms described above against active correlation attacks.

#arXiv #ResearchPapers #TorKameleon #Tor #CensorshipResistance #Privacy #CovertChannels
__
¹ https://arxiv.org/abs/2303.17544

J. Vilalonga et al., "TorKameleon: Improving Tor's Censorship Resistance With K-anonimization and Media-based Covert Channels"¹

The use of anonymity networks such as Tor and similar tools can greatly enhance the privacy and anonymity of online communications. Tor, in particular, is currently the most widely used system for ensuring anonymity on the Internet. However, recent research has shown that Tor is vulnerable to correlation attacks carried out by state-level adversaries or colluding Internet censors. Therefore, new and more effective solutions emerged to protect online anonymity. Promising results have been achieved by implementing covert channels based on media traffic in modern anonymization systems, which have proven to be a reliable and practical approach to defend against powerful traffic correlation attacks. In this paper, we present TorKameleon, a censorship evasion solution that better protects Tor users from powerful traffic correlation attacks carried out by state-level adversaries. TorKameleon can be used either as a fully integrated Tor pluggable transport or as a standalone anonymization system that uses K-anonymization and encapsulation of user traffic in covert media channels. Our main goal is to protect users from machine and deep learning correlation attacks on anonymization networks like Tor. We have developed the TorKameleon prototype and performed extensive validations to verify the accuracy and experimental performance of the proposed solution in the Tor environment, including state-of-the-art active correlation attacks. As far as we know, we are the first to develop and study a system that uses both anonymization mechanisms described above against active correlation attacks.

#arXiv #ResearchPapers #TorKameleon #Tor #CensorshipResistance #Privacy #CovertChannels
__
¹ https://arxiv.org/abs/2303.17544

J. Vilalonga et al., "TorKameleon: Improving Tor's Censorship Resistance With K-anonimization and Media-based Covert Channels"¹

The use of anonymity networks such as Tor and similar tools can greatly enhance the privacy and anonymity of online communications. Tor, in particular, is currently the most widely used system for ensuring anonymity on the Internet. However, recent research has shown that Tor is vulnerable to correlation attacks carried out by state-level adversaries or colluding Internet censors. Therefore, new and more effective solutions emerged to protect online anonymity. Promising results have been achieved by implementing covert channels based on media traffic in modern anonymization systems, which have proven to be a reliable and practical approach to defend against powerful traffic correlation attacks. In this paper, we present TorKameleon, a censorship evasion solution that better protects Tor users from powerful traffic correlation attacks carried out by state-level adversaries. TorKameleon can be used either as a fully integrated Tor pluggable transport or as a standalone anonymization system that uses K-anonymization and encapsulation of user traffic in covert media channels. Our main goal is to protect users from machine and deep learning correlation attacks on anonymization networks like Tor. We have developed the TorKameleon prototype and performed extensive validations to verify the accuracy and experimental performance of the proposed solution in the Tor environment, including state-of-the-art active correlation attacks. As far as we know, we are the first to develop and study a system that uses both anonymization mechanisms described above against active correlation attacks.

#arXiv #ResearchPapers #TorKameleon #Tor #CensorshipResistance #Privacy #CovertChannels
__
¹ https://arxiv.org/abs/2303.17544

M. Gross et al., "CPU to FPGA Power Covert Channel in FPGA-SoCs"¹

FPGA-SoCs are a popular platform for accelerating a wide
range of applications due to their performance and flexibility. From a
security point of view, these systems have been shown to be vulnerable
to various attacks, especially side-channel attacks where an attacker can
obtain the secret key of a cryptographic algorithm via laboratory mea-
surement equipment or even remotely with sensors implemented inside
the FPGA logic itself. Fortunately, a variety of countermeasures on the
algorithmic level have been proposed to mitigate this threat. Beyond side-
channel attacks, covert channels constitute another threat which enables
communication through a hidden channel. In this work, we demonstrate
the possibility of implementing a covert channel between the CPU and
an FPGA by modulating the usage of the Power Distribution Network.
We show that this resource is especially vulnerable since it can be easily
controlled and observed, resulting in a stealthy communication and a
high transmission data rate. The power usage is modulated using simple
and inconspicuous instructions executed on the CPU. Additionally, we
use Time-to-Digital Converter sensors to observe these power variations.
The sensor circuits are programmed into the FPGA fabric using only
standard logic components. Our covert channel achieves a transmission
rate of up to 16.7 kbit/s combined with an error rate of 2.3%. Besides
a good transmission quality, our covert channel is also stealthy and can
be used as an activation function for a hardware trojan.

#IACR #ResearchPapers #FPGA-SoCs #CovertChannels #PowerDistributionNetwork #OnChipPowerSensors #HardwareTrojan
__
¹ https://eprint.iacr.org/2023/429

M. Gross et al., "CPU to FPGA Power Covert Channel in FPGA-SoCs"¹

FPGA-SoCs are a popular platform for accelerating a wide
range of applications due to their performance and flexibility. From a
security point of view, these systems have been shown to be vulnerable
to various attacks, especially side-channel attacks where an attacker can
obtain the secret key of a cryptographic algorithm via laboratory mea-
surement equipment or even remotely with sensors implemented inside
the FPGA logic itself. Fortunately, a variety of countermeasures on the
algorithmic level have been proposed to mitigate this threat. Beyond side-
channel attacks, covert channels constitute another threat which enables
communication through a hidden channel. In this work, we demonstrate
the possibility of implementing a covert channel between the CPU and
an FPGA by modulating the usage of the Power Distribution Network.
We show that this resource is especially vulnerable since it can be easily
controlled and observed, resulting in a stealthy communication and a
high transmission data rate. The power usage is modulated using simple
and inconspicuous instructions executed on the CPU. Additionally, we
use Time-to-Digital Converter sensors to observe these power variations.
The sensor circuits are programmed into the FPGA fabric using only
standard logic components. Our covert channel achieves a transmission
rate of up to 16.7 kbit/s combined with an error rate of 2.3%. Besides
a good transmission quality, our covert channel is also stealthy and can
be used as an activation function for a hardware trojan.

#IACR #ResearchPapers #FPGA-SoCs #CovertChannels #PowerDistributionNetwork #OnChipPowerSensors #HardwareTrojan
__
¹ https://eprint.iacr.org/2023/429

M. Gross et al., "CPU to FPGA Power Covert Channel in FPGA-SoCs"¹

FPGA-SoCs are a popular platform for accelerating a wide
range of applications due to their performance and flexibility. From a
security point of view, these systems have been shown to be vulnerable
to various attacks, especially side-channel attacks where an attacker can
obtain the secret key of a cryptographic algorithm via laboratory mea-
surement equipment or even remotely with sensors implemented inside
the FPGA logic itself. Fortunately, a variety of countermeasures on the
algorithmic level have been proposed to mitigate this threat. Beyond side-
channel attacks, covert channels constitute another threat which enables
communication through a hidden channel. In this work, we demonstrate
the possibility of implementing a covert channel between the CPU and
an FPGA by modulating the usage of the Power Distribution Network.
We show that this resource is especially vulnerable since it can be easily
controlled and observed, resulting in a stealthy communication and a
high transmission data rate. The power usage is modulated using simple
and inconspicuous instructions executed on the CPU. Additionally, we
use Time-to-Digital Converter sensors to observe these power variations.
The sensor circuits are programmed into the FPGA fabric using only
standard logic components. Our covert channel achieves a transmission
rate of up to 16.7 kbit/s combined with an error rate of 2.3%. Besides
a good transmission quality, our covert channel is also stealthy and can
be used as an activation function for a hardware trojan.

#IACR #ResearchPapers #FPGA-SoCs #CovertChannels #PowerDistributionNetwork #OnChipPowerSensors #HardwareTrojan
__
¹ https://eprint.iacr.org/2023/429

M. Gross et al., "CPU to FPGA Power Covert Channel in FPGA-SoCs"¹

FPGA-SoCs are a popular platform for accelerating a wide
range of applications due to their performance and flexibility. From a
security point of view, these systems have been shown to be vulnerable
to various attacks, especially side-channel attacks where an attacker can
obtain the secret key of a cryptographic algorithm via laboratory mea-
surement equipment or even remotely with sensors implemented inside
the FPGA logic itself. Fortunately, a variety of countermeasures on the
algorithmic level have been proposed to mitigate this threat. Beyond side-
channel attacks, covert channels constitute another threat which enables
communication through a hidden channel. In this work, we demonstrate
the possibility of implementing a covert channel between the CPU and
an FPGA by modulating the usage of the Power Distribution Network.
We show that this resource is especially vulnerable since it can be easily
controlled and observed, resulting in a stealthy communication and a
high transmission data rate. The power usage is modulated using simple
and inconspicuous instructions executed on the CPU. Additionally, we
use Time-to-Digital Converter sensors to observe these power variations.
The sensor circuits are programmed into the FPGA fabric using only
standard logic components. Our covert channel achieves a transmission
rate of up to 16.7 kbit/s combined with an error rate of 2.3%. Besides
a good transmission quality, our covert channel is also stealthy and can
be used as an activation function for a hardware trojan.

#IACR #ResearchPapers #FPGA-SoCs #CovertChannels #PowerDistributionNetwork #OnChipPowerSensors #HardwareTrojan
__
¹ https://eprint.iacr.org/2023/429