The Experts below are selected from a list of 117 Experts worldwide ranked by ideXlab platform
Georg Carle - One of the best experts on this subject based on the ideXlab platform.
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NOMS - Hardening X.509 Certificate Issuance using Distributed Ledger Technology
NOMS 2020 - 2020 IEEE IFIP Network Operations and Management Symposium, 2020Co-Authors: Holger Kinkelin, Richard Von Seck, Christoph Rudolf, Georg CarleAbstract:The security of cryptographic communication protocols that use X.509 Certificates depends on the correctness of those Certificates. This paper proposes a system that helps to ensure the correct operation of an X.509 certification authority and its registration authorities. We achieve this goal by enforcing a policy-defined, multi-party validation and authorization workflow of Certificate signing requests. Besides, our system offers full accountability for this workflow for forensic purposes. As a foundation for our implementation, we leverage the distributed ledger and smart contract framework Hyperledger Fabric. Our implementation inherits the strong tamper-resistance of Fabric which strengthens the integrity of the computer processes that enforce the validation and authorization of the Certificate signing request, and of the metadata collected during Certificate Issuance.
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In Log We Trust: Revealing Poor Security Practices with Certificate Transparency Logs and Internet Measurements
Passive and Active Measurement, 2018Co-Authors: Oliver Gasser, Max Helm, Benjamin Hof, Ralph Holz, Maciej Korczynski, Georg CarleAbstract:In recent years, multiple security incidents involving Certificate Authority (CA) misconduct demonstrated the need for strengthened Certificate Issuance processes. Certificate Transparency (CT) logs make the Issuance publicly traceable and auditable.In this paper, we leverage the information in CT logs to analyze if Certificates adhere to the industry’s Baseline Requirements. We find 907 k Certificates in violation of Baseline Requirements, which we pinpoint to issuing CAs. Using data from active measurements we compare Certificate deployment to logged Certificates, identify non-HTTPS Certificates in logs, evaluate CT-specific HTTP headers, and augment IP address hitlists using data from CT logs. Moreover, we conduct passive and active measurements to carry out a first analysis of CT’s gossiping and pollination approaches, finding low deployment. We encourage the reproducibility of network measurement research by publishing data from active scans, measurement programs, and analysis tools.
Holger Kinkelin - One of the best experts on this subject based on the ideXlab platform.
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NOMS - Hardening X.509 Certificate Issuance using Distributed Ledger Technology
NOMS 2020 - 2020 IEEE IFIP Network Operations and Management Symposium, 2020Co-Authors: Holger Kinkelin, Richard Von Seck, Christoph Rudolf, Georg CarleAbstract:The security of cryptographic communication protocols that use X.509 Certificates depends on the correctness of those Certificates. This paper proposes a system that helps to ensure the correct operation of an X.509 certification authority and its registration authorities. We achieve this goal by enforcing a policy-defined, multi-party validation and authorization workflow of Certificate signing requests. Besides, our system offers full accountability for this workflow for forensic purposes. As a foundation for our implementation, we leverage the distributed ledger and smart contract framework Hyperledger Fabric. Our implementation inherits the strong tamper-resistance of Fabric which strengthens the integrity of the computer processes that enforce the validation and authorization of the Certificate signing request, and of the metadata collected during Certificate Issuance.
Richard Von Seck - One of the best experts on this subject based on the ideXlab platform.
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NOMS - Hardening X.509 Certificate Issuance using Distributed Ledger Technology
NOMS 2020 - 2020 IEEE IFIP Network Operations and Management Symposium, 2020Co-Authors: Holger Kinkelin, Richard Von Seck, Christoph Rudolf, Georg CarleAbstract:The security of cryptographic communication protocols that use X.509 Certificates depends on the correctness of those Certificates. This paper proposes a system that helps to ensure the correct operation of an X.509 certification authority and its registration authorities. We achieve this goal by enforcing a policy-defined, multi-party validation and authorization workflow of Certificate signing requests. Besides, our system offers full accountability for this workflow for forensic purposes. As a foundation for our implementation, we leverage the distributed ledger and smart contract framework Hyperledger Fabric. Our implementation inherits the strong tamper-resistance of Fabric which strengthens the integrity of the computer processes that enforce the validation and authorization of the Certificate signing request, and of the metadata collected during Certificate Issuance.
Christoph Rudolf - One of the best experts on this subject based on the ideXlab platform.
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NOMS - Hardening X.509 Certificate Issuance using Distributed Ledger Technology
NOMS 2020 - 2020 IEEE IFIP Network Operations and Management Symposium, 2020Co-Authors: Holger Kinkelin, Richard Von Seck, Christoph Rudolf, Georg CarleAbstract:The security of cryptographic communication protocols that use X.509 Certificates depends on the correctness of those Certificates. This paper proposes a system that helps to ensure the correct operation of an X.509 certification authority and its registration authorities. We achieve this goal by enforcing a policy-defined, multi-party validation and authorization workflow of Certificate signing requests. Besides, our system offers full accountability for this workflow for forensic purposes. As a foundation for our implementation, we leverage the distributed ledger and smart contract framework Hyperledger Fabric. Our implementation inherits the strong tamper-resistance of Fabric which strengthens the integrity of the computer processes that enforce the validation and authorization of the Certificate signing request, and of the metadata collected during Certificate Issuance.
Nadim Kobeissi - One of the best experts on this subject based on the ideXlab platform.
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Financial Cryptography - Formal Modeling and Verification for Domain Validation and ACME
Financial Cryptography and Data Security, 2017Co-Authors: Karthikeyan Bhargavan, Antoine Delignat-lavaud, Nadim KobeissiAbstract:Web traffic encryption has shifted from applying only to sensitive websites (such as banks) to a majority of all Web requests. Until recently, one of the main limiting factors for enabling HTTPS was the requirement to obtain a valid Certificate from a trusted certification authority. This process traditionally involves steps such as paying a Certificate Issuance fee, ad-hoc private key and Certificate request generation, and domain validation procedures. To remove this barrier of entry, the Internet Security Research Group (ISRG) introduced “Let’s Encrypt”, a new non-profit Certificate authority that uses a new protocol called Automatic Certificate Management Environment (ACME) to automate Certificate management at all levels (request, validation, Issuance, renewal, and revocation) between clients (website operators) and servers (Certificate authority nodes). Let’s Encrypt’s success is measured by its Issuance of over 27 million free Certificates since its launch in April 2016. In this paper, we survey the existing process for issuing domain-validated Certificates in major certification authorities. Based on our findings, we build a security model of domain-validated Certificate Issuance. We then model the ACME protocol in the applied pi-calculus and verify its stated security goals against our security model. We compare the effective security of different domain validation methods and show that ACME can be secure under a stronger threat model than that of traditional CAs. We also uncover weaknesses in some flows of ACME 1.0 and propose verified improvements that have been adopted in the latest protocol draft submitted to the IETF.
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A Formal Model for ACME: Analyzing Domain Validation over Insecure Channels
2016Co-Authors: Karthikeyan Bhargavan, Antoine Delignat-lavaud, Nadim KobeissiAbstract:Web traffic encryption has shifted from applying only to highly sensitive websites (such as banks) to a majority of all Web requests. Until recently, one of the main limiting factors for enabling HTTPS is the requirement to obtain a valid Certificate from a trusted certification authority, a tedious process that typically involves fees and ad-hoc key generation, Certificate request and domain validation procedures. To remove this barrier of entry, the Internet Security Research Group created Let's Encrypt, a new non-profit Certificate authority which uses a new protocol called Automatic Certificate Management Environment (ACME) to automate Certificate management at all levels (request, validation , Issuance, renewal, and revocation) between clients (website operators) and servers (Certificate authority nodes). Let's Encrypt's success is measured by its Issuance of over 12 million free Certificates since its launch in April 2016. In this paper, we survey the existing process for issuing domain-validated Certificates in major certification authorities to build a security model of domain-validated Certificate Issuance. We then model the ACME protocol in the applied pi-calculus and verify its stated security goals against our threat model of domain validation. We compare the effective security of different domain validation methods and show that ACME can be secure under a stronger threat model than that of traditional CAs. We also uncover weaknesses in some flows of ACME 1.0 and propose verified improvements that have been adopted in the latest protocol draft submitted to the IETF.
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Formal Modeling and Verification for Domain Validation and ACME
2016Co-Authors: Karthikeyan Bhargavan, Antoine Delignat-lavaud, Nadim KobeissiAbstract:Web traffic encryption has shifted from applying only to highly sensitive websites (such as banks) to a majority of all Web requests. Until recently, one of the main limiting factors for enabling HTTPS is the requirement to obtain a valid Certificate from a trusted certification authority, a tedious process that typically involves fees and ad-hoc key generation, Certificate request and domain validation procedures. To remove this barrier of entry, the Internet Security Research Group created Let's Encrypt, a new non-profit Certificate authority which uses a new protocol called Automatic Certificate Management Environment (ACME) to automate Certificate management at all levels (request, validation , Issuance, renewal, and revocation) between clients (website operators) and servers (Certificate authority nodes). Let's Encrypt's success is measured by its Issuance of over 12 million free Certificates since its launch in April 2016. In this paper, we survey the existing process for issuing domain-validated Certificates in major certification authorities to build a security model of domain-validated Certificate Issuance. We then model the ACME protocol in the applied pi-calculus and verify its stated security goals against our threat model of domain validation. We compare the effective security of different domain validation methods and show that ACME can be secure under a stronger threat model than that of traditional CAs. We also uncover weaknesses in some flows of ACME 1.0 and propose verified improvements that have been adopted in the latest protocol draft submitted to the IETF.