Password managers provide significant security benefits to users. However, malicious client-side scripts and browser extensions can steal passwords after the manager has autofilled them into the web page. In this paper, we extend prior work by Stock and Johns, showing how password autofill can be hardened to prevent these local attacks. We implement our design in the Firefox browser and conduct experiments demonstrating that our defense successfully protects passwords from XSS attacks and malicious extensions. We also show that our implementation is compatible with 97% of the Alexa top 1000 websites. Next, we generalize our design, creating a second defense that prevents recently discovered local attacks against the FIDO2 protocols. We implement this second defense into Firefox, demonstrating that it protects the FIDO2 protocol against XSS attacks and malicious extensions. This defense is compatible with all websites, though it does require a small change (2-3 lines) to web servers implementing FIDO2.

Lattice-based homomorphic encryption schemes provide strong resistance against quantum and classical computer-based adversary security attacks. In this article, we present a software-hardware co-design of two partially homomorphic encryption (PHE) schemes employing an ARM-System on Chip (ARM-SoC) and an field programmable gate array (FPGA). This provides necessary acceleration to PHE methods in the ecosystem mentioned above. The first PHE scheme is designed for generic homomorphic encryption, while the second scheme is aimed at resource optimized lightweight IoT-driven applications. For seamless assimilation, a robust and reliable low latency data transfer protocol is developed between the FPGA-based accelerator IP and ARM-SoC host system. The proposed PHE schemes are realized using Verilog hardware description language on multiple FPGA platforms. The proposed lightweight scheme is$52.71\times$more resource-efficient than the pipelined BGV RLWE-based method. It exhibits$1.43\times$and$1.29\times$better throughput than non-pipelined and pipelined realizations of the BGV RLWE-based scheme. The proposed hardware accelerators realized on FPGA platforms having lesser clock speed and consuming lower resources showcase significant speedup compared to their software implementations making our proposed method an efficient alternative to enhance security in edge-enabled IoT devices.

Popular instant messaging applications such as WhatsApp and Signal provide end-to-end encryption for billions of users. These applications often rely on a centralized, application-specific server to distribute public keys and relay encrypted messages between the users. As a result, they prevent passive attacks but are vulnerable to some active attacks. A malicious or hacked server can distribute fake keys to users to perform man-in-the-middle or impersonation attacks. While typical secure messaging applications provide a manual method for users to detect these attacks, this burdens users, and studies show it is ineffective in practice. This paper presents KTACA, a completely automated approach for key verification that is oblivious to users and easy to deploy. We motivate KTACA by designing two approaches to automatic key verification. One approach uses client auditing (KTCA) and the second uses anonymous key monitoring (AKM). Both have relatively inferior security properties, leading to KTACA, which combines these approaches to provide the best of both worlds. We provide a security analysis of each defense, identifying which attacks they can automatically detect. We implement the active attacks to demonstrate they are possible, and we also create a prototype implementation of all the defenses to measure their performance and confirm their feasibility. Finally, we discuss the strengths and weaknesses of each defense, the load they impose on clients and service providers, and their deployment considerations.

Today, some applications encrypt our data, while many others do not. Users must accept the level of protection the application provides. Our research aims to support client-to-client encryption at the system level so that users can enable encryption for data in any application (e.g., email, Slack), even if the application does not support it. Two users can exchange sensitive data without it being accessible to any applications or systems along the path. We will describe the challenges to designing the system, the techniques we will use to build the system, and the advantages of encryption at the system level.

Email is a critical Internet application, and its security is important. The Sender Policy Framework (SPF), DomainKeys Identified Mail (DKIM), and Domain-based Message Authentication, Reporting, and Conformance (DMARC) were developed to enable mail servers to detect and reject email coming from fraudulent sources. In this paper we study the state of SPF, DKIM, and DMARC validation across a large number of mail servers, the first such study at scale that we know of. We consider two behaviors of sender-validating mail servers: behavior when an email with a valid sender is received and behavior when an email from a invalid sender is received. Our techniques allow us to elicit SPF, DKIM, and DMARC validation behavior of the servers without spam. We find that as many as 85% of mail servers are deploying SPF validation, and over half are deploying all three mechanisms: SPF, DKIM, and DMARC. We also observe there are some nuanced behaviors with regard to adherence to the SPF specification.