Results 221 to 230 of about 4,544 (261)

An Improved Steganography Covert Channel

2009
An improved steganographic method is proposed in this paper. Two distinct methods are combined to achieve possibly high data hiding capability with high visual quality. The proposed method shifts the last n nonzero AC coefficients from S JPEG block, and changes the magnitude values of the first n nonzero AC coefficients from T JPEG blocks.
Md. Amiruzzaman, Hassan Peyravi, Mohammad Abdullah-Al-Wadud, Yoojin Chung   +3 more
openaire   +1 more source

The Dilemma of Covert Channels Searching

2006
Covert channel is a famous drawback exists in most of multilevel security systems. Both TESEC and CC standards need covert channel analysis when secure software tries to get the certification of some security levels, i.e. B2 and EAL5 or above in TCSEC and CC, respectively.
Changda Wang 0001, Shiguang Ju
openaire   +1 more source

Characterization of Covert Channels in DNS

2014 6th International Conference on New Technologies, Mobility and Security (NTMS), 2014
Malware families utilize different protocols to establish their covert communication networks. It is also the case that sometimes they utilize protocols which are least expected to be used for transferring data, e.g., Domain Name System (DNS). Even though the DNS protocol is designed to be a translation service between domain names and IP addresses, it
Hamad Binsalleeh, A. Mert Kara, Amr M. Youssef, Mourad Debbabi   +3 more
openaire   +1 more source

Covert channel analysis for Stubs

1996
This paper explains a range of techniques for covert channel control for the Stubs network security devices. The techniques deal with both timing and storage channels, and rely on a combination of channel elimination, reduction, and audit mechanisms. Although specific to the Stubs system, the techniques of analysis and control are adaptable to similar ...
Mark S. Anderson 0001, Maris A. Ozols
openaire   +1 more source

Concurrent Covert Communication Channels

2010
This paper introduces a new steganographic technique in which a set of concurrent hidden channels are established between a sender and multiple receivers. Each channel is protected by a separate key. The method can work with JPEG blocks in which an 8 × 8 block is divided into four non-overlapping sets, each consisting a covert channel that hides a ...
Md. Amiruzzaman, Hassan Peyravi, Mohammad Abdullah-Al-Wadud, Yoojin Chung   +3 more
openaire   +1 more source

Multi-Covert Channel Attack in the Cloud

2019 Sixth International Conference on Software Defined Systems (SDS), 2019
Frequently, it is believed that the adoption of encryption is adequate to ensure the safety of the message. However, encryption only restricts unapproved individuals from decoding the message. Whereas in many circumstances, the mere presence of communication or variations in communication patterns, such as an increase in message rate, is sufficient to ...
Akil M., Mancini L. V., Venturi D.
openaire   +1 more source

On the Formal Characterization of Covert Channel

2004
This paper presents a formal characterization model for covert channel. Some characteristic properties are proposed. The system characteristics are used to guide the development of covert channel identification and elimination algorithms. In addition, we audit a covert channel and evaluate the developed algorithms quantitatively with our formalism.
Shiguang Ju, Xiaoyu Song
openaire   +1 more source

The covert channel limiter revisited

ACM SIGOPS Operating Systems Review, 1989
In a previous article 1 , I introduced the idea of a mechanism (the covert channel limiter) that would watch for the potential uses of covert channels and affect the responsible process (or process group) only when such potential uses exceeded the allowable bandwidth for covert channels.
openaire   +1 more source

Lattice scheduling and covert channels

Proceedings 1992 IEEE Computer Society Symposium on Research in Security and Privacy, 2003
The lattice scheduler is a process scheduler that reduces the performance penalty of certain covert-channel countermeasures by scheduling processes using access class attributes. The lattice scheduler was developed as part of the covert-channel analysis of the VAX security kernel. The VAX security kernel is a virtual-machine monitor security kernel for
openaire   +1 more source

Covert channels in LAN protocols

1989
Encryption is generally understood as being the basic mechanisms for LAN security. However, usage of encryption finds its limitations in case of an unauthorized information flow via covert channels. Some covert storage and timing channels inherent in a LAN's architecture are already described in the literature. This paper takes a more general approach.
openaire   +1 more source