skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


Title: A Complete Study of P.K.I. (PKI’s Known Incidents)
In this work, we report on a comprehensive analysis of PKI resulting from Certificate Authorities’ (CAs) behavior using over 1300 instances. We found several cases where CAs designed business models that favored the issuance of digital certificates over the guidelines of the CA Forum, root management programs, and other PKI requirements. Examining PKI from the perspective of business practices, we identify a taxonomy of failures and identify systemic vulnerabilities in the governance and practices in PKI. Notorious cases include the “backdating” of digital certificates, the issuance of these for MITM attempts, the lack of verification of a requester’s identity, and the unscrupulous issuance of rogue certificates. We performed a detailed study of 379 of these 1300 incidents. Using this sample, we developed a taxonomy of the different types of incidents and their causes. For each incident, we determined if the incident was disclosed by the problematic CA. We also noted the Root CA and the year of the incident. We identify the failures in terms of business practices, geography, and outcomes from CAs. We analyzed the role of Root Program Owners (RPOs) and differentiated their policies. We identified serial and chronic offenders in the PKI trusted root programs. Some of these were distrusted by RPOs, while others remain being trusted despite failures. We also identified cases where the concentration of power of RPOs was arguably a contributing factor in the incident. We identify these cases where there is a risk of concentration of power and the resulting conflict of interests. Our research is the first comprehensive academic study addressing all verified reported incidents. We approach this not from a machine learning or statistical perspective but, rather, we identify each reported public incident with a focus on identifying patterns of individual lapses. Here we also have a specific focus on the role of CAs and RPOs. Building on this study, we identify the issues in incentive structures that are contributors to the problems.  more » « less
Award ID(s):
1814518
PAR ID:
10204025
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
SSRN Electronic Journal
Volume:
TPRC
Issue:
47
ISSN:
1556-5068
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; ; ; (, 2020 43rd International Conference on Telecommunications and Signal Processing (TSP))
    Blockchain technology is the cornerstone of digital trust and systems’ decentralization. The necessity of eliminating trust in computing systems has triggered researchers to investigate the applicability of Blockchain to decentralize the conventional security models. Specifically, researchers continuously aim at minimizing trust in the well-known Public Key Infrastructure (PKI) model which currently requires a trusted Certificate Authority (CA) to sign digital certificates. Recently, the Automated Certificate Management Environment (ACME) was standardized as a certificate issuance automation protocol. It minimizes the human interaction by enabling certificates to be automatically requested, verified, and installed on servers. ACME only solved the automation issue, but the trust concerns remain as a trusted CA is required. In this paper we propose decentralizing the ACME protocol by using the Blockchain technology to enhance the current trust issues of the existing PKI model and to eliminate the need for a trusted CA. The system was implemented and tested on Ethereum Blockchain, and the results showed that the system is feasible in terms of cost, speed, and applicability on a wide range of devices including Internet of Things (IoT) devices. 
    more » « less
  2. ; ; ; ; ; ; ; ; ; ; et al (, CCS '19: Proceedings of the 2019 ACM SIGSAC Conference on Computer and Communications Security)
    null (Ed.)
    Let's Encrypt is a free, open, and automated HTTPS certificate authority (CA) created to advance HTTPS adoption to the entire Web. Since its launch in late 2015, Let's Encrypt has grown to become the world's largest HTTPS CA, accounting for more currently valid certificates than all other browser-trusted CAs combined. By January 2019, it had issued over 538 million certificates for 223 million domain names. We describe how we built Let's Encrypt, including the architecture of the CA software system (Boulder) and the structure of the organization that operates it (ISRG), and we discuss lessons learned from the experience. We also describe the design of ACME, the IETF-standard protocol we created to automate CA--server interactions and certificate issuance, and survey the diverse ecosystem of ACME clients, including Certbot, a software agent we created to automate HTTPS deployment. Finally, we measure Let's Encrypt's impact on the Web and the CA ecosystem. We hope that the success of Let's Encrypt can provide a model for further enhancements to the Web PKI and for future Internet security infrastructure. 
    more » « less
  3. ; ; ; (, SSRN Electronic Journal)
    null (Ed.)
    The Public Key Infrastructure (PKI) is the foundation which enables secure and trusted transactions across the Internet. PKI is subject to both continuous attacks and regular improvements; for example, advances in cryptography have led to rejections of previously trusted algorithms (i.e., SHA1, MD5). Yet there have also been organizational failures and malicious acts by trusted parties. In this work, we focus on the sociotechnical components of the current X.509 PKI with the goals of better understanding its vulnerabilities, and ideally informing the implementation of future PKIs. We begin with a taxonomy of chronic, catastrophic, high impact, or frequent PKI failures. This categorization was informed by a survey of non-expert perceptions of PKI and an interdisciplinary workshop addressing the future of security in the Internet of Things. To evaluate the failure modes, we conducted qualitative interviews with policy scholars and experts in applied cryptography. We summarize the results of the survey and workshop, and detail the expert interviews. Our findings indicate that there are significant failure types which neither the technical nor policy community are deeply engaging. The underlying assumptions about rate and severity of failure differ between these communities. Yet there is a common awareness of the vulnerabilities of the end users: the people who are required to trust PKI to interact and engage with the Internet. We identify an urgency in mitigating such critical issues, because of the increasing adoption of cyberphysical systems and the Internet of Things (IoT). We concluded that there is a need for integrated organizational, policy, and technical coordination to address the chronic and potentially catastrophic risks. We introduce possible economic and regulatory solutions, and highlight the key takeaways which pave our future research directions. 
    more » « less
  4. ; ; ; ; (, International Conference on Computer Communications and Networks (ICCCN))
    Public Key Infrastructure (PKI) generates and distributes digital certificates to provide the root of trust for securing digital networking systems. To continue securing digital networking in the quantum era, PKI should transition to use quantum-resistant cryptographic algorithms. The cryptography community is developing quantum-resistant primitives/algorithms, studying, and analyzing them for cryptanalysis and improvements. National Institute of Standards and Technology (NIST) selected finalist algorithms for the post-quantum digital signature cipher standardization, which are Dilithium, Falcon, and Rainbow. We study and analyze the feasibility and the processing performance of these algorithms in memory/size and time/speed when used for PKI, including the key generation from the PKI end entities (e.g., a HTTPS/TLS server), the signing, and the certificate generation by the certificate authority within the PKI. The transition to post-quantum from the classical ciphers incur changes in the parameters in the PKI, for example, Rainbow I significantly increases the certificate size by 163 times when compared with RSA 3072. Nevertheless, we learn that the current X.509 supports the NIST post-quantum digital signature ciphers and that the ciphers can be modularly adapted for PKI. According to our empirical implementations-based study, the post-quantum ciphers can increase the certificate verification time cost compared to the current classical cipher and therefore the verification overheads require careful considerations when using the post-quantum-cipher-based certificates. 
    more » « less
  5. ; ; ; ; (, Annual Computer Security Applications Conference)
    null (Ed.)
    Many recent proposals to increase the resilience of the Web PKI against misbehaving CAs face significant obstacles to deployment. These hurdles include (1) the requirement of drastic changes to the existing PKI players and their interactions, (2) the lack of signaling mechanisms to protect against downgrade attacks, (3) the lack of an incremental deployment strategy, and (4) the use of inflexible mechanisms that hinder recovery from misconfiguration or from the loss or compromise of private keys. As a result, few of these proposals have seen widespread deployment, despite their promise of a more secure Web PKI. To address these roadblocks, we propose Certificates with Automated Policies and Signaling (CAPS), a system that leverages the infrastructure of the existing Web PKI to overcome the aforementioned hurdles. CAPS offers a seamless and secure transition away from today’s insecure Web PKI and towards present and future proposals to improve the Web PKI. Crucially, with CAPS, domains can take simple steps to protect themselves from MITM attacks in the presence of one or more misbehaving CAs, and yet the interaction between domains and CAs remains fundamentally the same. We implement CAPS and show that it adds at most 5% to connection establishment latency. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email