PKI Consortium blog

Posts by tag Revocation

    What Is Certificate Transparency and How Does It Propose to Address Certificate Mis-Issuance?
    September 9, 2013 by CA Security Council Attack Mis-issued OCSP Revocation SSL/TLS TSA

    As originally architected by Netscape and others in the mid-1990s, the certificate issuance process envisioned that the CA would present the certificate and its contents to the named subject who would review and accept the certificate first. Then the CA would publish the certificate to a repository. That process would establish that the certificate’s subject was aware of certificate issuance. (Otherwise, an unscrupulous CA could sign a subscriber’s public key and create a certificate for the subscriber without its knowledge.) The repository was also an independent means of obtaining and verifying the public key prior to initiating secure, authenticated communication without having to obtain it solely from the server during session negotiation.

    An Introduction to OCSP Multi-Stapling
    May 7, 2013 by CA Security Council CA/Browser Forum CRL IETF OCSP Revocation SSL/TLS Vulnerability

    OCSP Stapling

    OCSP is a protocol used to check the validity of certificates to make sure they have not been revoked. OCSP is an alternative to Certificate Revocation Lists (CRLs). Since OCSP responses can be as small as a few hundred bytes, OCSP is particularly useful when the issuing CA has relatively big CRLs, as well as when the client has limited memory and processing power.

    Recap of NIST’s Workshop on Improving Trust in the Online Marketplace
    April 17, 2013 by Rick Andrews CA/Browser Forum CASC NIST Revocation SSL/TLS

    On April 10 and 11, NIST held a workshop in Maryland to bring together many parties (industry, research and academia communities, and government sectors) to examine “technical and administrative efforts to increase trust online by improving the Public Key Infrastructure certificate marketplace supporting SSL and TLS.”

    From the opening keynote to the final remarks, we heard from experts around the world. There were presentations on the current state of trust infrastructure and audits, the impact of recent breaches, detailed looks on some emerging solutions like Certificate Transparency and DANE, and new ideas to manage and minimize risk in key usage.

    IETF 86 – Web PKI Working Group
    March 21, 2013 by Bruce Morton (Entrust) CRL Google IETF OCSP PKI Policy Revocation SSL/TLS Web PKI

    At the IETF 86 meeting in Orlando last week, there was a working group meeting discussing the operations of the Web PKI. At the previous IETF 85 meeting a birds-of-a-feather was held to discuss the purpose of having such a group. The result of the meeting was an established group with the charter that states purposes such as:

    • Working group will work to improve the consistency of Web security behavior
    • Address problems as seen by the end-users, certificate holders and CAs
    • Describe how the Web PKI actually works
    • Prepare documented deliverables as discussed below

    The meeting discussed the charter and the four following deliverables. More information is in the presentation slides; look under the Operations and Management Area, then under WPKOPS.

    The Importance of Revocation Checking Part 2: A Real World Example
    March 11, 2013 by Wayne Thayer Attack Code Signing CRL Encryption Identity Malware OCSP Revocation SSL/TLS

    Just last week, a new security incident related to certificate revocation checking made headlines. It was discovered that a legitimate website was hosting a malicious Java application that installed malware on the computers of people who visited the site. This comes after recent updates that introduced Security Level settings in Java, and then raised the default from Medium to High. At the high level, users are shown a warning before any unsigned Java code is executed. Unfortunately, this recent incident exposed a method that allows an attacker to bypass the warning.

    The Importance of Checking for Certificate Revocation
    March 9, 2013 by Rick Andrews Attack CRL Identity Malware MITM OCSP Revocation SSL/TLS

    Certificates are typically valid for one to three years, and during that time it’s possible that the web site owner or the CA realizes that end users should not trust the certificate. There are several cases in which this might happen, including these:

    • The web site owner ceases doing business, no longer owns the domain name used in the certificate, has changed their organization name, or wishes to shut down the web server.
    • The subscriber learns that an unauthorized party has gained access to the private key associated with the public key in the certificate.
    • The CA learns that errors were made in authentication, the subscriber misrepresented some material info used in the authentication process, or the subscriber has violated the terms of its agreement with the CA.

    When the subscriber or CA makes the decision to revoke a certificate, that decision must be conveyed to end users who encounter the certificate in use. There are two different methods for this:

    OCSP Stapling: Improved Performance and Security, a Win-Win
    February 14, 2013 by Jeremy Rowley CASC OCSP Revocation SSL/TLS

    The launch of the CASC has given its members a unique platform through which we can educate users about online security and the best practices in utilizing SSL. That’s why we’ve decided to pair the group’s launch with a focused effort on OCSP stapling.

    Why OCSP stapling? For one, stapling is already supported by IIS and the newest versions of Apache and nginx. Although server software does not enable OCSP by default, servers can be re-configured with a little education. OCSP stapling is a significant improvement on traditional CRLs and OCSP revocation mechanisms because it eliminates the communication between the browser and CA when establishing the SSL connection. This leads to an increase in browsing performance and eliminates an attacker’s ability to successfully block a CA’s ability to provide revocation information. Stapled OCSP responses are cached by the web administrator and sent back to the relying party during the communication, effectively reducing bandwidth requirements and speeding up the SSL connection.

    Certificate Revocation and OCSP Stapling
    February 14, 2013 by CA Security Council Attack CASC CRL IETF OCSP Revocation SSL/TLS

    Revocation

    As a body of global CAs, the CA Security Council is committed to educating server administrators, end-users and other interested parties about SSL enhancements and best practices that can better protect everyone. An important initiative that can make a practical difference right now is addressing easily implemented improvements to certificate status services that handle revocation of invalid or expired certificates, specifically the implementation of OCSP stapling.

    World’s Leading Certificate Authorities Come Together to Advance Internet Security and the Trusted SSL Ecosystem
    February 14, 2013 by CA Security Council CA/Browser Forum CASC CRL OCSP Revocation SSL/TLS

    San Francisco, CA. – February 14, 2013 – Leading global certificate authorities announced the creation of the Certificate Authority Security Council (CASC), an advocacy group, committed to the exploration and promotion of best practices that advance the security of websites and online transactions. Through public education, collaboration, and advocacy, the CASC strives to improve understanding of critical policies and their potential impact on the internet infrastructure. Members of the CASC include Comodo, DigiCert, Entrust, GlobalSign, Go Daddy, Symantec, and Trend Micro.

    Participate in our community discussions and/or join the consortium