With the rapid growth of software services and applications, the need to secure digital assets became paramount. The introduction of Password Manager (PM) and Virtual Private Network (VPN) software was established as a prerequisite toolkit to bolster the end-user arsenal. As a matter of fact, these types of artifacts have been around for at least 25 years in various flavors, including desktop and browser-based applications. This work assesses the ability of 12 desktop PM applications, 5 browsers with integrated PM, and 12 PMs in the form of browser plugins, along with 21 VPN client applications, to effectively protect the confidentiality of secret credentials. Our analysis focuses on the period during which an app is loaded into RAM. Despite the sensitive nature of these applications, our results show that across all scenarios the majority of PM applications store plaintext passwords in the system memory; more specifically, 75% (or 9 out of 12) of desktop PM applications, 100% (5 out of 5) of browser PMs and 75% (or 9 out of 12) of PM browser plugins leak such sensitive information. In addition, 33% (or 7 out of 21) of VPN applications leak user credentials. This practice of storing cleartext sensitive information in system memory is widely recognized as a weakness, having also been registered as CWE-316. At the time of writing, merely four vendors have recognized our exploits as vulnerabilities. Three of these vendors have assigned the relevant Common Vulnerabilities and Exposures (CVE) IDs, namely CVE-2023-23349, CVE-2024-9203, and CVE-2024-50570, whereas the fourth one will issue a CVE ID once it implements the relevant fixes. The remaining vendors have either chosen to disregard or downplay the severity of this issue.

Abstract Password management has long been a persistently challenging task. This led to the introduction of password management software, which has been around for at least 25 years in various forms, including desktop and browser-based applications. This work assesses the ability of two dozen password managers, 12 desktop applications, and 12 browser plugins, to effectively protect the confidentiality of secret credentials in six representative scenarios. Our analysis focuses on the period during which a Password Manager (PM) resides in the RAM. Despite the sensitive nature of these applications, our results show that across all scenarios, only three desktop PM applications and two browser plugins do not store plaintext passwords in the system memory. Oddly enough, at the time of writing, only two vendors recognized the exploit as a vulnerability, reserving CVE-2023-23349, while the rest chose to disregard or underrate the issue.

Being on a mushrooming spree since at least 2013, malware can take a large toll on any system. In a perpetual cat-and-mouse chase with defenders, malware writers constantly conjure new methods to hide their code so as to evade detection by security products. In this context, focusing on the MS Windows platform, this work contributes a comprehensive empirical evaluation regarding the detection capacity of popular, off-the-shelf antivirus and endpoint detection and response engines when facing legacy malware obfuscated via more or less uncommon but publicly known methods. Our experiments exploit a blend of seven traditional AV evasion techniques in 16 executables built in C++, Go, and Rust. Furthermore, we conduct an incipient study regarding the ability of the ChatGPT chatbot in assisting threat actors to produce ready-to-use malware. The derived results in terms of detection rate are highly unexpected: approximately half of the 12 tested AV engines were able to detect less than half of the malware variants, four AVs exactly half of the variants, while only two of the rest detected all but one of the variants.

Following QUIC protocol ratification on May 2021, the third major version of the Hypertext Transfer Protocol, namely HTTP/3, was published around one year later in RFC 9114. In light of these consequential advancements, the current work aspires to provide a full-blown coverage of the following issues, which to our knowledge have received feeble or no attention in the literature so far. First, we provide a complete review of attacks against HTTP/2, and elaborate on if and in which way they can be migrated to HTTP/3. Second, through the creation of a testbed comprising the at present six most popular HTTP/3-enabled servers, we examine the effectiveness of a quartet of attacks, either stemming directly from the HTTP/2 relevant literature or being entirely new. This scrutiny led to the assignment of at least one CVE ID with a critical base score by MITRE. No less important, by capitalizing on a realistic, abundant in devices testbed, we compiled a voluminous, labeled corpus containing traces of ten diverse attacks against HTTP and QUIC services. An initial evaluation of the dataset mainly by means of machine learning techniques is included as well. Given that the 30 GB dataset is made available in both pcap and CSV formats, forthcoming research can easily take advantage of any subset of features, contingent upon the specific network topology and configuration.

During 2021, different worldwide initiatives have been established for the development of digital vaccination certificates to alleviate the restrictions associated with the COVID‐19 pandemic to vaccinated individuals. Although diverse technologies can be considered for the deployment of such certificates, the use of blockchain has been suggested as a promising approach due to its decentralization and transparency features. However, the proposed solutions often lack realistic experimental evaluation that could help to determine possible practical challenges for the deployment of a blockchain platform for this purpose. To fill this gap, this work introduces a scalable, blockchain‐based platform for the secure sharing of COVID‐19 or other disease vaccination certificates. As an indicative use case, we emulate a large‐scale deployment by considering the countries of the European Union. The platform is evaluated through extensive experiments measuring computing resource usage, network response time, and bandwidth. Based on the results, the proposed scheme shows satisfactory performance across all major evaluation criteria, suggesting that it can set the pace for real implementations. Vis‐à‐vis the related work, the proposed platform is novel, especially through the prism of a large‐scale, full‐fledged implementation and its assessment.

The coronavirus pandemic is a new reality, and it severely affects the modus vivendi of the international community. In this context, governments are rushing to devise or embrace novel surveillance mechanisms and monitoring systems to fight the outbreak. The development of digital tracing apps, which among others are aimed at automatising and globalising the prompt alerting of individuals at risk in a privacy-preserving manner, is a prominent example of this ongoing effort. Very promptly, a number of digital contact tracing architectures have been sprouted, followed by relevant app implementations adopted by governments worldwide. Bluetooth, specifically its Low Energy (BLE) power-conserving variant, has emerged as the most promising short-range wireless network technology to implement the contact tracing service. This work offers the first to our knowledge full-fledged review of the most concrete contact tracing architectures proposed so far in a global scale. This endeavour does not only embrace the diverse types of architectures and systems, namely, centralised, decentralised, or hybrid, but also equally addresses the client side, i.e., the apps that have been already deployed in Europe by each country. There is also a full-spectrum adversary model section, which does not only amalgamate the previous work in the topic but also brings new insights and angles to contemplate upon.

This study advances research in offensive technology by proposing return oriented programming (ROP) as a means to achieve code obfuscation. The key inspiration is that ROP's unique structure poses various challenges to malware analysis compared to traditional shellcode inspection and detection. The proposed ROP‐based attack vector provides two unique features: (i) the ability to automatically analyse and generate equivalent ROP chains for a given code, and (ii) the ability to reuse legitimate code found in an executable in the form of ROP gadgets. To this end, a software tool named ROPInjector was developed which, given any piece of shellcode and any legitimate executable file, it transforms the shellcode to its ROP equivalent re‐using the available code in the executable and finally patches the ROP chain infecting the executable. After trying various combinations of evasion techniques, the results show that ROPInjector can evade nearly and completely all antivirus software employed in the online VirusTotal service, making ROP an effective ingredient for code obfuscation. This attack vector poses a serious threat which malicious actors can take advantage to perform cyber‐attack campaigns.

Anonymity on SIP signaling can be achieved either by the construction of a lower level tunnel (via the use of SSL or IPSec protocols) or by employing a custom-tailored solution. Unfortunately, the former category of solutions present significant impediments including the requirement for a PKI and the hop-by-hop fashioned protection, while the latter only concentrate on the application layer, thus neglecting sensitive information leaking from lower layers. To remediate this problem, in the context of this paper, we employ the well-known Tor anonymity system to achieve complete SIP traffic obfuscation from an attacker's standpoint. Specifically, we capitalize on Tor for preserving anonymity on network links that are considered mostly untrusted, i.e., those among SIP proxies and the one between the last proxy in the chain and the callee. We also, combine this Tor-powered solution with PrivaSIP to achieve an even greater level of protection. By employing PrivaSIP we assure that: (a) the first hop in the path (i.e., between the caller and the outbound proxy) affords anonymity, (b) the callee does not know the real identity of the caller, and (c) no real identities of both the caller and the callee are stored in log files. We also evaluate this scheme in terms of performance and show that even in the worst case, the latency introduced is not so high as it might be expected due to the use of Tor.

The Session Initiation Protocol (SIP) is a signaling protocol for the creation, modification and termination of multimedia sessions with one or more participants. While SIP operates in highly dynamic environments such as Next Generation Networks, in current deployments its access control support is based on traditional access control models. The main problem these models face is that under certain circumstances they tend to be inadequate in current highly dynamic environments. Usage Control is an access control model that supports the same functionalities as traditional models do, but further introduce novel ones. In a previous work, an architecture supporting continuous authorization on SIP based on the Usage Control model was presented. Here this architecture is further elaborated, described in more detail and experimentally evaluated.

Abstract In the near future, wireless heterogeneous networks are expected to interconnect in an all‐IP architecture. An open issue towards this direction is the uninterrupted continuation of the received services during handover between networks employing different access technologies. In this context, Mobile IP (MIP) is a protocol that allows fast and secure handovers. However, MIP per se cannot handle all the issues that surface during handovers in certain services, and more specifically, when the information of the current state of a service requires re‐establishment on the new subnet without having to repeat the entire protocol exchange with the mobile host from the outset. A number of methods have been proposed to solve the aforementioned problem, commonly referred to as secure context transfer. However, while such methods do succeed in minimising the disruption caused by security‐related delays, it seems that little has been done to protect the end‐users' privacy as well. In this paper, a number of privacy enhanced (PE) context transfer schemes are presented. The first two of them have been introduced in a previous work of ours while the other two are novel. All schemes are analysed in terms of message exchange and evaluated through simulations. The performance of our schemes is compared with the standard ones proposed by the Seamoby work group (WG). The results demonstrate that the proposed schemes are very efficient in terms of application handover times, while at the same time guarantee the privacy of the end‐user. Copyright © 2010 John Wiley & Sons, Ltd.

The growing demand for voice services and multimedia delivery over the Internet has raised SIPpsilas popularity making it a subject of extensive research. SIP is an application layer control signaling protocol, whose main purpose is to create, modify and terminate multimedia sessions. Research has shown that SIP has a number of security issues that must be solved in order to increase its trustworthiness and supersede or coexist with PSTN. In this paper our purpose is to address such a weakness, namely the caller identity privacy issue. While some solutions to this problem do exist, we will show that they are inadequate in a number of situations. Furthermore, we will propose a novel scheme for the protection of callerpsilas identity which can also support roaming between different administrative domains. Finally, we provide some performance results, which demonstrate that the proposed solution is efficient even in low-end mobile devices.

In the future 4G wireless networks will span across different administrative domains. In order to provide secure seamless handovers in such an environment the context transfer protocol is an attractive solution. However, the aforementioned protocol arises some privacy issues concerning the location and movement of users roaming between administrative domains. The purpose of this paper is to present and analyze these privacy issues and propose two privacy enhanced context transfer schemes that alleviate these problems. In the first scheme the Mobile Node (MN) is responsible for the transmission of the context to the new domain. In the second scheme the Home Domain (HD) of the user forwards the context acting as a proxy between the old and the new domain. While the second scheme is expected to be more useful towards realizing seamless handovers, the first one poses less signaling load to the HD. In addition, assuming that the most appropriate form of user identity for the context is the Network Access Identifier (NAI), we show how the employment of temporary NAIs can further increase the privacy of our schemes.