A certificate vendor notified a company that recently invalidated certificates may need to be updated. Which of the following mechanisms should a security administrator use to determine whether the certificates installed on the company's machines need to be updated?
The most appropriate mechanism for determining whether the certificates installed on the company's machines need to be updated is the Online Certificate Status Protocol (OCSP). OCSP allows for real-time, online verification of the status of a digital certificate by querying the issuing Certificate Authority (CA) or an OCSP responder. This is ideal for checking the revocation status of certificates, especially if they have been recently invalidated, as it provides immediate and accurate information about the certificate's validity without the latency involved in downloading and parsing a Certificate Revocation List (CRL).
OCSP real-time and online, CRL offline and has delays
The language of the questions force me to say CRL. If they had OCSP, the vendor will not need to notify and it would have been done real-time and no intervention from admin. Therefore, this question will not exist. ChatGPT You're right. Based on the context provided, if OCSP was in place and functioning correctly, the revocation status would be determined in real-time, reducing the need for manual intervention from the admin upon vendor notification. The scenario described—where the certificate vendor notifies the company about invalidated certificates—does suggest a more manual or batch process of checking revocation, which aligns with the use of CRLs. Your interpretation makes sense, and in this context, CRL is indeed the more fitting choice for the scenario described in the question.
you think too much. scenario: OCSP may not be available at certain time and that's why there is a reminder email. And now, OCSP is available again, so admin can verify it online.
From a practical standpoint, an administrator would use automation to compare all existing certificates with the revocation list, but potentially they could also script to OCSP per each certificate in the environment. Either option seem valid, but CRL seems the better option from enterprise scan perspective. Prove me wrong with CompTIA docs, not ChatGPT.
Yet again I don't like the context of the question, however I am inclined to go with OCSP. CRL's are certainly more efficient when bandwidth is being considered, as OCSP can generate lots of traffic. So why not CRL? In these situations where I'm initially 50/50 and am forced to make an inference, I try to ask myself what the exam authors are attempting to test us on. In the question, it specifically mentions that the certificates are "recently" invalidated. Wth does recently mean? The CRL could be updated every 24 hours, but if "recently" means they were officially invalidated 2 hours ago, then the CRL is useless. Bandwidth and network concerns are not mentioned at all in the question stem, so even though everyone is making great points about benefits of CRL, I submit that the relevant piece of information is the indication of wanting real-time results. Hence, OCSP
Here's why: OCSP (Online Certificate Status Protocol) is a protocol used to check the revocation status of digital certificates. When a certificate vendor notifies a company that certificates may need to be updated, it often implies that there could be a revocation or expiration issue with the certificates. OCSP allows the security administrator to check the real-time status of the certificates by querying the issuing Certificate Authority (CA) or an OCSP responder to verify whether the certificates are still valid. CRL (Certificate Revocation List) is a list of revoked certificates published by a CA. While CRLs contain information about revoked certificates, they may not always provide real-time status updates, unlike OCSP.
Certificate Revocation List (CRL) - A CRL is a list of revoked certificates that is downloaded from the Certificate Authority (CA). Online Certificate Status Protocol (OCSP) - OCSP is a protocol for checking revocation of a single certificate interactively using an online service called an OCSP responder.
Keyword: Mechanism. CRL is just a list, but OCSP is a protocol and aligns better as a mechanism.
I would go with B because CRL might be outdated. And it clearly says "Recently" in the question which means there is a good chance the revoked certs are not in the list. Refer to this: "When a CA receives a CRL request from a browser, it returns a complete list of all the revoked certificates that the CA manages. The browser must then parse the list to determine if the certificate of the requested site has been revoked. CRLs are often updated weekly or daily and, in some cases, hourly."
Given the scenario described, the most appropriate mechanism for determining whether the certificates installed on the company's machines need to be updated is option B, OCSP. OCSP enables real-time checking of certificate validity, allowing the security administrator to verify whether the invalidated certificates need to be updated promptly.
From Mike Meyers’ Sec + 601 Certification Guide “The Online Certificate Status Protocol (OCSP) is used to automate certificate validation, making checking the status of certificates seamless and transparent to the user. Most modern browsers and other applications that use digital certificates can use OCSP to check CRLs automatically for certificate validity. OCSP permits users (through Internet browser and other certificate-aware applications) to check for certificate expiration, suspension, and revocation before the certificate is accepted.” “The CA publishes a certificate revocation list (CRL) that contains the certificates the entity has issued and subsequently revoked. Users can access this list to determine the validity of a certificate. If a certificate has been revoked, it is considered no longer valid and cannot be used. CRLs can be published online, or they can be part of an automated process that application software checks from a centralized repository.”
Based on the situation provided the answer is D. CRL The question mentioned that the company needs to determine whether the certificates installed on their machines need to be updated. This implies a bulk check of certificates across multiple machines rather than individual certificates being checked in real-time. While OCSP could be used for this purpose by querying the CA for each installed certificate, it might not be the most efficient approach, especially for a large number of certificates or for periodic checks. Certificate Revocation Lists (CRLs) are typically used for batch checking of certificate revocation status across multiple certificates.
I associate OCSP with online and CRL with offline.
OCSP which is Online Certificate Status Protocol, is a method for checking the revocation status of certificates in real time. OCSP servers and CRLs (Certificate Revocation Lists) both serve the same function, but OCSP is more efficient and faster than CRLs. CRLs are lists of revoked certificates that are periodically updated by the Certificate Authority (CA). OCSP eliminates the need to download and store large CRL files, and provides more accurate and timely information about the validity of certificates.
The security administrator should use the Certificate Revocation List (CRL) to determine whether the certificates installed on the company’s machines need to be updated. The CRL is a list of digital certificates that have been revoked by the issuing Certificate Authority (CA) before their scheduled expiration date.
My Reason for going with OCSP: OCSP security is a protocol used to discover the revocation status of a certificate and contains signatures that assert a certificate has not been revoked. This makes it a more effective and efficient validation process, as it does not require a list to be downloaded to discover the status of a certificate. A CRL is a list containing serial numbers of all certificates that have been revoked by a CA. However, CRLs can present issues, as they can become outdated and have to be downloaded. So there OCSP will be more suitable in this case. Folks make sure when you see some of these questions, do you research!
B. OCSP (Online Certificate Status Protocol) The Online Certificate Status Protocol (OCSP) is a mechanism used to check the revocation status of a digital certificate. When a certificate vendor notifies a company that certificates may need to be updated, the security administrator can use OCSP to verify whether the certificates installed on the company's machines are still valid or have been revoked. Option D, CRL (Certificate Revocation List), is also relevant for checking the revocation status of certificates. However, OCSP provides a more real-time approach, as it allows the client to check the status of a certificate directly with the Certificate Authority (CA) instead of downloading and checking a potentially large list of revoked certificates. Therefore, while both OCSP and CRL are mechanisms for checking certificate revocation, OCSP is often considered more efficient in certain scenarios.
The only thong that make me choose CRL over OSCP is the questions states certificates. We dont know how many. OSCP = 1 at a time, CRL = multiple. They are both valid answers but which is more specific
Let's take a look. CRL: Lists all revoked certificates issued by a CA. Suitable when multiple verifications are required. Useful in case of network failures if the CRL is saved offline. OCSP: Only suitable for checking single a single certificate at a time. Won't work if the OCSP is down.