The European General Data Protection Regulation (GDPR) grants European users the right to access their data processed and stored by organizations. Although the GDPR contains requirements for data processing organizations (e.g., understandable data provided within a month), it leaves much flexibility. In-depth research on how online services handle data subject access request is sparse. Specifically, it is unclear whether online services comply with the individual GDPR requirements, if the privacy policies and the data subject access responses are coherent, and how the responses change over time. To answer these questions, we perform a qualitative structured review of the processes and data exports of significant online services to (1) analyze the data received in 2023 in detail, (2) compare the data exports with the privacy policies, and (3) compare the data exports from November 2018 and November 2023. The study concludes that the quality of data subject access responses varies among the analyzed services, and none fulfills all requirements completely.

Security situational awareness refers to identifying, mitigating, and preventing digital cyber threats by gathering information to understand the current situation. With awareness, the basis for decisions is present, particularly in complex situations. However, while logging can track the successful login into a system, it typically cannot determine if the login was performed by the user assigned to the account. An account takeover, for example, by a successful phishing attack, can be used as an entry into an organization's network. All identities within an organization are managed in an identity management system. Thereby, these systems are an interesting goal for malicious actors. Even within identity management systems, it is difficult to differentiate legitimate from malicious actions. We propose a security situational awareness approach specifically to identity management. We focus on protocol-specifics and identity-related sources in a general concept before providing the example of the protocol OAuth with a proof-of-concept implementation.

Abstract While self-sovereign identities (SSI) have been gaining more traction, the topic of SSI security has yet to be addressed. Especially regarding response procedures to security incidents, no prior work is available. However, incident response processes are essential to systematically respond to a security incident in a timely manner. We first evaluate the current state-of-the-art by conducting a literature survey and contacting organizations that offer SSI. The insights underpin the subject’s relevance, highlighting that incident response capabilities are just starting to be developed. Contributing to this development, we identify the challenges of building a security incident response process for SSI. Mainly, the decentralized nature inhibits the utilization of known best practices, which all focus on building a centralized incident response capability. However, even in the case of SSI, some centralized entities may exist. Therefore, we design two variants of SIR processes: one more centralized and one more decentralized. For the latter, the problem size is reduced in the first step by identifying all the stakeholders within an SSI ecosystem and then analyzing possible proactive and reactive measures each participant can access. This procedure leads to the grouping of SSI system participants into three distinct domains of incident response. For each domain, different capabilities for handling incidents are introduced depending on the involved stakeholders, their infrastructure, and their goals. To demonstrate the procedures, incident scenarios for each domain highlight the workflows during incident handling.

Identity management enables users to access services around the globe. The user information is managed in some sort of identity management system. With the proposed shift to self-sovereign identities, self-sovereign control is shifted to the individual user. However, this also includes responsibilities, for example, in case of incidents. This is the case although they typically do not have the capability to do so. In order to provide users with more control and less responsibilities, we unite identity management systems with public key infrastructures. This consolidation allows more flexible and customized trust relationships to be created and validated. This paper explains, analyzes, and validates our novel design for a Distributed Identity Information Network (DistIN) that allows a high degree of decentralization while aiming for high security, privacy, usability, scalability, and sovereignty. The primary advantage of the system lies in its flexibility and ease of use, which also enables smaller organizations or even private individuals to participate in the network with a service. This work compiles categorized requirements from the literature and analyzes the verification and authentication data flows. On this basis, the security analysis and validation are following. This work is an essential step to reach the goal of the final web-based DistIN protocol and application.

Phishing is a major cyber threat to organizations that can cause financial and reputational damage, threatening their existence. The technical measures against phishing should be complemented by awareness training for employees. However, there is little validation of awareness measures. Consequently, organizations have an additional burden when integrating awareness training, as there is no consensus on which method brings the best success. This paper examines how awareness concepts can be successfully implemented and validated. For this purpose, various factors, such as requirements and possible combinations of methods, are taken into account in our case study at a small- and medium-sized enterprise (SME). To measure success, phishing exercises are conducted. The study suggests that pleasant campaigns result in better performance in the simulated phishing exercise. In addition, significant improvements and differences in the target groups could be observed. The implementation of awareness training with integrated key performance indicators can be used as a basis for other organizations.

Data breaches resulting from targeted attacks against organizations, e. g., by advanced persistent threat groups, often involve social engineering (SE) as the initial attack vector before malicious software is used, e. g., for persistence, lateral movement, and data exfiltration. While technical security controls, such as the automated detection of phishing emails, can contribute to mitigating SE risks, raising awareness for SE attacks through education and motivation of personnel is an important building block to increasing an organization’s resilience. To facilitate hands-on SE awareness training as one component of broader SE awareness campaigns, we created a SE tabletop game called Tabletop As Social Engineering Prevention (TASEP) in two editions for (a) small and medium enterprises and (b) large corporations, respectively. Its game design is inspired by Dungeons & Dragons role-playing games and facilitates LEGO models of the in-game target organizations. Participants switch roles by playing a group of SE penetration testers and conducting a security audit guided by the game master. We evaluated the created game with different student groups, achieving highly immersive and flexible training, resulting in an entertaining way of learning about SE and raising awareness.

Risk-based authentication (RBA) aims to protect end-users against attacks involving stolen or otherwise guessed passwords without requiring a second authentication method all the time. Online services typically set limits on what is still seen as normal and what is not, as well as the actions taken afterward. Consequently, RBA monitors different features, such as geolocation and device during login. If the features’ values differ from the expected values, then a second authentication method might be requested. However, only a few online services publish information about how their systems work. This hinders not only RBA research but also its development and adoption in organizations. In order to understand how the RBA systems online services operate, black box testing is applied. To verify the results, we re-evaluate the three large providers: Google, Amazon, and Facebook. Based on our test setup and the test cases, we notice differences in RBA based on account creation at Google. Additionally, several test cases rarely trigger the RBA system. Our results provide new insights into RBA systems and raise several questions for future work.

The General Data Protection Regulation (GDPR) was implemented in 2018 to strengthen and harmonize the data protection of individuals within the European Union. One key aspect is Article 15, which gives individuals the right to access their personal data in an understandable format. Organizations offering services to Europeans had five years’ time to optimize their processes and functions to comply with Article 15. This study aims to explore the process of submitting and receiving the responses of organizations to GDPR Article 15 requests. A quantitative analysis obtains data from various websites to understand the level of conformity, the data received, and the challenges faced by individuals who request their data. The study differentiates organizations operating worldwide and in Germany, browser website- and app-based usage, and different types of websites. Thereby, we conclude that some websites still compile the data manually, resulting in longer waiting times. A few exceptions did not respond with any data or deliver machine-readable data (GDRP Article 20). The findings of the study additionally reveal ten patterns individuals face when requesting and accessing their data.

Password authentication is a weak point for security as passwords are easily stolen and a user may ignore the security by using a simple password. Therefore, services increasingly demand a second factor. While this may enhance security, it comes with a lower level of usability and another factor to be forgotten. A smartphone is an important device in daily life. With the growing number of sensors and features in a smartphone, keystroke dynamics may provide an easy-to-use method. In this paper, we introduce requirements for biometric authentication and keystroke dynamics. This results in an evaluation scheme, which is applied to three selected approaches. Based on the comparison, keystroke dynamics and the evaluation scheme are discussed. The obtained results indicate that keystroke dynamics can be used as another authentication method but can be bypassed by stronger adversaries. For further research, a common data set would improve the comparability.

Cyber attacks are ubiquitous and a constantly growing threat in the age of digitization. In order to protect important data, developers and system administrators must be trained and made aware of possible threats. Practical training can be used for students alike to introduce them to the topic. A constant threat to websites that require user authentication is so-called brute-force attacks, which attempt to crack a password by systematically trying every possible combination. As this is a typical threat, but comparably easy to detect, it is ideal for beginners. Therefore, three open-source blue team scenarios are designed and systematically described. They are contiguous to maximize the learning effect.

The increase of Internet services has not only created several digital identities but also more information available about the persons behind them. The data can be collected and used for attacks on digital identities as well as on identity management systems, which manage digital identities. In order to identify possible attack vectors and take countermeasures at an early stage, it is important for individuals and organizations to systematically search for and analyze the data. This paper proposes a classification of data and open-source intelligence (OSINT) tools related to identities. This classification helps to systematically search for data. In the next step, the data can be analyzed and countermeasures can be taken. Last but not least, an OSINT framework approach applying this classification for searching and analyzing data is presented and discussed.

Our everyday life depends more and more on online services and, therefore, access to related user accounts. The security of user accounts, again, is tied to the security of the corresponding primary and fallback authentication methods. Accounts can be linked to each other – by fallback authentication, through SSO, or by using the same authentication devices – creating an account network. These account networks enhance login comfort and are needed in case of account recovery, but they also increase each account's attack surface. In addition, misconfigurations might result in account inaccessibility. However, these problems can only be detected by analyzing single accounts first and then the resulting account networks. Despite the importance to understand account security and accessibility, almost no analysis methods exist. To address this need, this article presents the Authentication Analysis Framework (AAF). AAF evaluates account types and primary and fallback authentication methods for each account, before analyzing the overall account network. By detecting transitive risks, weak links can be discovered and subsequently strengthened. We further propose maturity models to rank the primary and fallback authentication methods based on risks and a description language to exchange the required information. AAF is implemented as a plugin for the password manager KeePass to assist end users and as a standalone tool for researchers.

User authentication is necessary for the majority of online services. If users fail to authenticate due to the loss of an authentication factor, fallback processes allow users to regain access to their accounts. However, most of the proposed and deployed fallback methods have substantial weaknesses that degrade security, e.g., guessable security questions. This is even more serious since through account dependencies (e.g., password reset via email), additional accounts can be compromised. On the other hand, misconfiguration of (fallback) authentication might result in locking a user out of an account.

Identity management refers to the technology and policies for the identification, authentication, and authorization of users in computer networks. Identity management is therefore fundamental to today’s IT ecosystem. At the same time, identity management systems, where digital identities are managed, pose an attractive target for attacks. With the heterogeneity of identity management systems, every type (i. e., models, protocols, implementations) has different requirements, typical problems, and hence attack vectors. In order to provide a systematic and categorized overview, the framework Taxonomy for Identity Management Attacks (TaxIdMA) for attacks related to identities is proposed. The purpose of this framework is to classify existing attacks associated with system identities, identity management systems, and end-user identities as well as the background using an extensible structure from a scientific perspective. The taxonomy is then evaluated with eight real-world attacks resp. vulnerabilities. This analysis shows the capability of the proposed taxonomy framework TaxIdMA in describing and categorizing these attacks.

In today’s networks, administrative access to Linux servers is commonly managed by Privileged Access Management (PAM). It is not only important to monitor these privileged accounts, but also to control segregation of duty and detect keys as well as accounts that potentially bypass PAM. Unprohibited access can become a business risk. In order to improve the security in a controlled manner, we establish IdMSecMan, a security management process tailored for identity and access management (IAM). Security management processes typically use the Deming Cycle or an adaption for continuous improvements of products, services, or processes within the network infrastructure. We adjust a security management process with visualization for IAM, which also shifts the focus from typical assets to the attacker. With the controlled cycles, the maturity of IAM is measured and can continually advance. This paper presents and applies the work in progress IdMSecMan to a motivating scenario in the field of Linux server. We evaluate our approach in a controlled test environment with first steps to roll it out in our data center. Last but not least, we discuss challenges and future work.

Identity and access management (I&AM) is the umbrella term for managing users and their permissions. It is required for users to access different services. These services can either be provided from their home organization, like a company or university, or from external service providers, e. g., cooperation partners. I&AM provides the management of identifiers with the attributes, credentials, roles, and permissions the user has. Today, the requirements have evolved from simply accessing individual web services in the internet or at a company to the majority of all IT services from different service providers with various accounts. Several identity management models have been created with different approaches within.

Awareness and knowledge management are key components to achieve a high level of information security in organizations. However, practical evidence suggests that there are significant discrepancies between the typical elements of security awareness campaigns, the decisions made and goals set by top-level management, and routine operations carried out by systems administration personnel. This paper presents Vis4Sec, a process framework for the generation and distribution of stakeholder-specific visualizations of security metrics, which assists in closing the gap between theoretical and practical information security by respecting the different points of view of the involved security report audiences. An implementation for patch management on Linux servers, deployed at a large data center, is used as a running example.