Student therapists\u27 use of self-disclosure with clients who have experienced trauma

Therapist self-disclosure is a controversial topic in that it has been historically and widely debated in past research and literature across theoretical orientations. Much of the existing self-disclosure research focuses on the effects that therapist self-disclosure has on the therapeutic relationship, using varied methodology in its definition and measurement of how, when, and in what context therapist self-disclosure is utilized. There are also very few studies that investigate frequency rates of therapist self-disclosure; of those that do exist, results are mixed. Additionally, there is little to no research on how self-disclosure is used by student therapists, in actual psychotherapy sessions, particularly in the context of sessions in which difficult or traumatic subject matter is discussed. Accordingly, the purpose of the present study was to qualitatively explore verbalizations of student therapist self-disclosure in psychotherapy sessions with trauma survivors. A sample of 5 therapist-participants from university-based community counseling centers were selected, and transcribed videotaped sessions in which client- and therapist-participants discussed trauma were analyzed. A qualitative and deductive content analysis was employed, using a coding system that was created based on the extant literature on therapist self-disclosure, to examine verbal expressions of therapist self-disclosure in psychotherapy sessions with trauma survivors. The results indicated that the therapist-participants used many different forms of self-disclosure (self-involving disclosures, disclosures that are not otherwise specified, personal self-disclosure, and demographic self-disclosures, in order of frequency) both within and out of trauma discussions. More specifically, self-involving disclosures (SINV-PERS) tended to occur more frequently within trauma discussions while personal and demographic disclosures (SDIS-PERS and SDIS-DEMO) tended to occur more frequently in non-trauma discussions. Therapist self-disclosures comprised 6 of the 9 proposed coding categories over all 5 psychotherapy sessions. It is hoped that this study will raise awareness around the issue of the use of therapist self-disclosure in psychotherapy, both in general and with clients who have experienced traumatic events during the course of their lives. The findings have implications for both future studies examining therapist self-disclosure as well as clinical training practices in graduate programs for student therapists, an area of study that is currently under-researched

Cryptanalysis of Symmetric Cryptographic Primitives

Symmetric key cryptographic primitives are the essential building blocks in modern information security systems. The overall security of such systems is crucially dependent on these mathematical functions, which makes the analysis of symmetric key primitives a goal of critical importance. The security argument for the majority of such primitives in use is only a heuristic one and therefore their respective security evaluation continually remains an open question. In this thesis, we provide cryptanalytic results for several relevant cryptographic hash functions and stream ciphers. First, we provide results concerning two hash functions: HAS-160 and SM3. In particular, we develop a new heuristic for finding compatible differential paths and apply it to the the Korean hash function standard HAS-160. Our heuristic leads to a practical second order collision attack over all of the HAS-160 function steps, which is the first practical-complexity distinguisher on this function. An example of a colliding quartet is provided. In case of SM3, which is a design that builds upon the SHA-2 hash and is published by the Chinese Commercial Cryptography Administration Office for the use in the electronic authentication service system, we study second order collision attacks over reduced-round versions and point out a structural slide-rotational property that exists in the function. Next, we examine the security of the following three stream ciphers: Loiss, SNOW 3G and SNOW 2.0. Loiss stream cipher is designed by Dengguo Feng et al. aiming to be implemented in byte-oriented processors. By exploiting some differential properties of a particular component utilized in the cipher, we provide an attack of a practical complexity on Loiss in the related-key model. As confirmed by our experimental results, our attack recovers 92 bits of the 128-bit key in less than one hour on a PC with 3 GHz Intel Pentium 4 processor. SNOW 3G stream cipher is used in 3rd Generation Partnership Project (3GPP) and the SNOW 2.0 cipher is an ISO/IEC standard (IS 18033-4). For both of these two ciphers, we show that the initialization procedure admits a sliding property, resulting in several sets of related-key pairs. In addition to allowing related-key key recovery attacks against SNOW 2.0 with 256-bit keys, the presented properties reveal non-random behavior of the primitives, yield related-key distinguishers for the two ciphers and question the validity of the security proofs of protocols based on the assumption that these ciphers behave like perfect random functions of the key-IV. Finally, we provide differential fault analysis attacks against two stream ciphers, namely, HC-128 and Rabbit. In this type of attacks, the attacker is assumed to have physical influence over the device that performs the encryption and is able to introduce random faults into the computational process. In case of HC-128, the fault model in which we analyze the cipher is the one in which the attacker is able to fault a random word of the inner state of the cipher but cannot control its exact location nor its new faulted value. Our attack requires about 7968 faults and recovers the complete internal state of HC-128 by solving a set of 32 systems of linear equations over Z2 in 1024 variables. In case of Rabbit stream cipher, the fault model in which the cipher is analyzed is the one in which a random bit of the internal state of the cipher is faulted, however, without control over the location of the injected fault. Our attack requires around 128 − 256 faults, precomputed table of size 2^41.6 bytes and recovers the complete internal state of Rabbit in about 2^38 steps

Cryptanalysis of symmetric key primitives

Block ciphers and stream ciphers are essential building blocks that are used to construct computing systems which have to satisfy several security objectives. Since the security of these systems depends on the security of its parts, the analysis of these symmetric key primitives has been a goal of critical importance. In this thesis we provide cryptanalytic results for some recently proposed block and stream ciphers. First, we consider two light-weight block ciphers, TREYFER and PIFEA-M. While TREYFER was designed to be very compact in order to fit into constrained environments such as smart cards and RFIDs, PIFEA-M was designed to be very fast in order to be used for the encryption of multimedia data. We provide a related-key attack on TREYFER which recovers the secret key given around 2 11 encryptions and negligible computational effort. As for PIFEA-M, we provide evidence that it does not fulfill its design goal, which was to defend from certain implementation dependant differential attacks possible on previous versions of the cipher. Next. we consider the NGG stream cipher, whose design is based on RC4 and aims to increase throughput by operating with 32-bit or 64-bit values instead of with 8-bit values. We provide a distinguishing attack on NGG which requires just one keystream word. We also show that the first few kilobytes of the keystream may leak information about the secret key which allows the cryptanalyst to recover the secret key in an efficient way. Finally, we consider GGHN, another RC4-like cipher that operates with 32-bit words. We assess different variants of GGHN-Iike algorithms with respect to weak states, in which all internal state words and output elements are even. Once GGHN is absorbed in such a weak state, the least significant bit of the plaintext words will be revealed only by looking at the ciphertext. By modelling the algorithm by a Markov chain and calculating the chain absorption time, we show that the average number of steps required by these algorithms to enter this weak state can be lower than expected at first glance and hence caution should be exercised when estimating this numbe

Analysis of Boomerang Differential Trails via a SAT-Based Constraint Solver URSA

In order to obtain differential patterns over many rounds of a cryptographic primitive, the cryptanalyst often needs to work on local differential trail analysis. Examples include merging two differential trail parts into one or, in the case of boomerang and rectangle attacks, connecting two short trails within the quartet boomerang setting. In the latter case, as shown by Murphy in 2011, caution should be exercised as there is increased chance of running into contradictions in the middle rounds of the primitive. In this paper, we propose the use of a SAT-based constraint solver URSA as aid in analysis of differential trails and find that previous rectangle/boomerang attacks on XTEA and SHACAL-1 block ciphers and SM3 hash function are based on incompatible trails. Given the C specification of the cryptographic primitive, verifying differential trail portions requires minimal work on the side of the cryptanalyst

On the sliding property of SNOW 3G and SNOW 2.0

SNOW 3G is a stream cipher chosen by the 3rd Generation Partnership Project (3GPP) as a crypto-primitive to substitute KASUMI in case its security is compromised. SNOW 2.0 is one of the stream ciphers chosen for the ISO/IEC standard IS 18033-4. In this study, the authors show that the initialisation procedure of the two ciphers admits a sliding property, resulting in several sets of related-key pairs. In case of SNOW 3G, a set of 232 related-key pairs is presented, whereas in the case of SNOW 2.0, several such sets are found, out of which the largest are of size 264 and 2192 for the 128-bit and 256-bit variant of the cipher, respectively. In addition to allowing related-key recovery attacks against SNOW 2.0 with 256-bit keys, the presented properties reveal non-random behaviour that yields related-key distinguishers and also questions the validity of the security proofs of protocols that are based on the assumption that SNOW 3G and SNOW 2.0 behave like perfect random functions of the key-IV

Boomerang and Slide-Rotational Analysis of the SM3 Hash Function

SM3 is a hash function designed by Xiaoyun Wang et al., and published by the Chinese Commercial Cryptography Administration Office for the use of electronic authentication service system. The design of SM3 builds upon the design of the SHA-2 hash function, but introduces additional strengthening features. In this paper, using a higher order differential cryptanalysis approach, we present a practical 4-sum distinguisher against the compression function of SM3 reduced to 32 rounds. In addition, we point out a slide-rotational property of SM3-XOR, which exists due to the fact that constants used in the rounds are not independent

Rebound attacks on stribog

Abstract. In August 2012, the Stribog hash function was selected as the new Russian hash standard (GOST R 34.11-2012). Stribog is an AES-based primitive and is considered as an asymmetric reply to the new SHA-3. In this paper we investigate the collision resistance of the Stribog compression function and its internal cipher. Specifically, we present a message differential path for the internal block cipher that allows us to efficiently obtain a 5-round free-start collision and a 7.75 free-start near collision for the internal cipher with complexities 2 8 and 2 40 , respectively. Finally, the compression function is analyzed and a 7.75 round semi freestart collision, 8.75 and 9.75 round semi free-start near collisions are presented along with an example for 4.75 round 50 out of 64 bytes near colliding message pair

A heuristic for finding compatible differential paths with application to HAS-160

The question of compatibility of differential paths plays a central role in second order collision attacks on hash functions. In this context, attacks typically proceed by starting from the middle and constructing the middle-steps quartet in which the two paths are enforced on the respec- tive faces of the quartet structure. Finding paths that can fit in such a quartet structure has been a major challenge and the currently known compatible paths extend over a suboptimal number of steps for hash functions such as SHA-2 and HAS-160. In this paper, we investigate a heuristic that searches for compatible differential paths. The application of the heuristic in case of HAS-160 yields a practical second order collision over all of the function steps, which is the first practical result that covers all of the HAS-160 steps. An example of a colliding quartet is provide

The use of remote monitoring of cardiac implantable devices during the COVID-19 pandemic: an EHRA physician survey

It is unclear to what extent the COVID-19 pandemic has influenced the use of remote monitoring (RM) of cardiac implantable electronic devices (CIEDs). The present physician-based European Heart Rhythm Association (EHRA) survey aimed to assess the influence of the COVID-19 pandemic on RM of CIEDs among EHRA members and how it changed the current practice. The survey comprised 27 questions focusing on RM use before and during the pandemic. Questions focused on the impact of COVID-19 on the frequency of in-office visits, data filtering, reasons for initiating in-person visits, underutilization of RM during COVID-19, and RM reimbursement. A total of 160 participants from 28 countries completed the survey. Compared to the pre-pandemic period, there was a significant increase in the use of RM in patients with pacemakers (PMs) and implantable loop recorders (ILRs) during the COVID-19 pandemic (PM 24.2 vs. 39.9%, P = 0.002; ILRs 61.5 vs. 73.5%, P = 0.028), while there was a trend towards higher utilization of RM for cardiac resynchronization therapy-pacemaker (CRT-P) devices during the pandemic (44.5 vs. 55%, P = 0.063). The use of RM with implantable cardioverter-defibrillators (ICDs) and CRT-defibrillator (CRT-D) did not significantly change during the pandemic (ICD 65.2 vs. 69.6%, P = 0.408; CRT-D 65.2 vs. 68.8%, P = 0.513). The frequency of in-office visits was significantly lower during the pandemic (P < 0.001). Nearly two-thirds of participants (57 out of 87 respondents), established new RM connections for CIEDs implanted before the pandemic with 33.3% (n = 29) delivering RM transmitters to the patient's home address, and the remaining 32.1% (n = 28) activating RM connections during an in-office visit. The results of this survey suggest that the crisis caused by COVID-19 has led to a significant increase in the use of RM of CIEDs