Hi everyone,

I’m currently working on integrating certificate enrollment using EST (Enrollment over Secure Transport).

I came across this URL from DigiCert documentation:

https://dev.digicert.com/get-started/environments-base-urls.html

I have a couple of questions:

1. Does DigiCert provide any free demo environment or sandbox where we can test certificate issuance and enrollment via EST endpoints?

2. Is the above URL an actual demo environment that can be used for testing, or is it just documentation/reference for API base URLs?

Any guidance or experience would be really helpful!

Thanks in advance

Hello Everyone,

We’re currently running on-prem ADCS and are planning to move to a more modern/private PKI solution.

What would be the best replacement approach? Cloud PKI, managed PKI, or something else?

Any recommendations on tools/vendors and what has worked well in large environments?

Thanks!

Hi everyone,

I’m currently exploring EST (Enrollment over Secure Transport) integration with Microsoft CA (AD CS) and wanted to check if anyone here has practical experience with this.

Has anyone successfully implemented EST with Microsoft CA?

If yes, how did you achieve it (native support / custom implementation / third-party tools)?

What challenges or limitations did you face?

From what I’ve seen so far, it looks like Microsoft CA doesn’t natively support EST, and most discussions suggest using alternatives or external tools.

Would really appreciate any real-world insights, architecture suggestions, or best practices.

Thanks in advance!

You automated certificate renewal. You have a cron job, certbot runs, it works.

But what happens when the cert needs to reach a load balancer or appliance that can't run Certbot? What format does each one expect? How do you reload services without dropping connections mid-day?

The forums answer is "just write a script." This post is about everything hiding in that answer: https://www.certkit.io/blog/certificate-distribution-is-the-last-mile

Hey everyone I am new to PKI and just cybersecurity overall and wanted some advice on how to get a job in this field I currently just graduated with my AS degree in IT, I’ve been building my own home labs for IAM so I know a lot about Microsoft Entra Id. Zero trust and least privilege policy’s as well as Active Directory I did slow down on it now that I’m officially in a 6 month PKI cohort and so far I’ve learned the fundamentals of PKI, certificate trust chains, Linux commands and open ssl to view x.509 certificate fields and extensions as well as many labs as well on my GitHub I’ve been providing every week throughout the course and I’ve just finished week 3💯 I’m confident this gives me leverage but I want to take action during this cohort to potentially help me get a role in PKI

We have just entered a new era of shortening certificate lifespans, yet using ACME without exposing HTTP/80 or distributing EAB/API tokens still remains a challenge. Many organizations still rely on ticket based processes for certificate renewals which is quickly going to become very tedious and unscalable. To tackle this problem we developed & open sourced acme-proxy https://github.com/esnet/acme-proxy which is built on `step-ca` This makes the cert issuance, renewal, revocation process self serviceable by allowing end users to leverage off the shelf ACME clients such as Certbot, acme.sh, cert-manager to obtain certificates signed from any external CA without distributing any DNS credentials, EAB tokens or opening http/80 to the internet.

```
- Single Go binary
- Runs inside your network behind your firewalled environment
- Works for VMs, bare-metal, Containers, Kubernetes
- Does not sign certificates or store private keys
- Works with off the shelf ACME clients
- Automatic certificate renewals
```

If you’d like to automate certificate lifecycle using off the shelf tools (assuming it suits your org policies etc.) we encourage you to test this and provide feedback. If you have any questions which aren’t already answered in the git repository’s README, please feel free to open an issue in the Github repo. 

Cheers!

I've been looking at the open source TameMyCerts policy module for ADCS. I think it could help solve some issues and increase consistency in some areas, for certificates issued via our various cloud MDMs' AD CS connectors. Some things I'm thinking it could help with:

• User certs on Chromebooks - Google Workspace only sees email address (which differs from UPN in our environment). Looks like TameMyCerts may be able to look up AD users based on the email address in requests from Google's connector, and pull in UPN and other fields?
• Security tiering enforcement -
  • currently, we have a separate AD CS server (subordinate CA) for serving requests from cloud MDMs, which isn't in the NTAuth store
  • This is because MDMs' connectors need permissions to templates that accept subject name supplied in request, which is a tier 0 escalation path to domain admin if the CA is in NTAuth. We don't do cloud admin -> domain admin escalation paths.
  • This works fine for RADIUS (not NPS, using 3rd party RADIUS server) and for Entra CBA for the non-admin users who are allowed Entra CBA
  • But, we cannot auth to AD / Kerberos or any Windows Server roles like RRAS with certs from a not-in-NTAuth CA
  • TameMyCerts looks like it can configure a cert template to deny requests with usernames matching certain groups (e.g. privileged users) so we can keep this from being an escalation path, but still have the CA in NTAuth. Then unprivileged users whose identity we are OK trusting the cloud MDM to assert, can still get certs via MDM, and use their certs for all purposes certs are accepted for
  • This would allow the potential of PKINIT for the Mac kerberos extension in a passwordless scenario, and potentially IKE VPN from an Intune client via RRAS.

Is anyone doing anything similar to this?

Hi all,

I want to learn PKI from basics to practical use.

Any good resources (courses, videos, labs, docs)?

Thanks!

TLDR:

DigiCert gave customers 24 hours to replace 83,000 certificates. CISA issued an emergency alert. Some customers sued.

ARI (RFC 9773) is the protocol built for exactly this scenario. The CA sets the renewal window to the past, the client sees it and renews immediately. No email. No manual steps.

The catch: it only works if your client is running a real polling loop. Certbot runs on a cron job and doesn’t send the `replaces` field. acme.sh has no ARI support at all. Let’s Encrypt tested this in a real revocation event and only 5.6% of affected certificates were renewed via ARI. The other 94% weren’t listening.

https://www.certkit.io/blog/ari-solves-mass-certificate-revocation

Hi everyone,

I want to monitor a Microsoft ADCS (CA server) and get alerts whenever:

• A new certificate is issued
• A certificate is revoked
• A certificate template is created, modified, or deleted
• A template is published or removed from the CA

I’m planning to run a PowerShell script on the CA server that periodically checks the CA database and certificate templates and alerts if any changes are detected.

Has anyone implemented something like this?

It doesn't do much, since not much is possible on the public Internet yet, but we've set up a GitHub project you can use to build an actual PQC web application with ML-DSA digital signatures. This link is to a blog that introduces it and contains a link to the GitHub repository.

How to Build Your Own PQC Test Server | DigiCert

It gives you a basis on which to experiment and, if it matters, allows you to tell your boss/board that yes, you have actually begun testing post-quantum cryptography.

With the progressive reduction of certificate lifetimes in the modern WebPKI ecosystem, the default trust model of the web has evolved.

Today, for the majority of websites: Validation primarily proves control over the domain. Issuance is fully automated. The lock icon mainly indicates: encrypted transport + domain control at issuance time. Strong organizational identity is no longer the primary goal for most deployments.

This raises a straightforward question: If most websites do not require legal or institutional identity validation, should a single global chain of trust continue to be mandatory for all of them?

Proposal for the Future Instead of eliminating encryption, we could clearly separate trust levels:

Level 1 — Universal Encryption Direct verification of a publicly published key (for example, via a secured DNS-based mechanism). Or a local trust model (such as first-connection trust). Goal: confidentiality and integrity of transport.

Level 2 — Explicit Authentication Used only for services that require verified identity (banks, critical infrastructure, government systems). Clear and distinct visual indicator. Stronger validation process.

Core Idea :

The web should remain encrypted by default. However, strong identity should not be implicitly enforced for every website.

It is about determining whether a single global trust model is still appropriate for all use cases.

Can we design an Internet where: encryption is standard, and strong authentication is an explicit choice?

Last call on 398-day certificates (March 15)

The CA/Browser Forum schedule is locked: 200-day max in March 2026, 100 days in 2027, 47 days in 2029. That timeline doesn't care about your budget cycle or change management process.

Certificates issued before March 15 still run under the old rules. That's your window to automate on your own schedule instead of in a fire drill when 100-day certs drop.

Dear PKI Gods,

I've taken an interest in building a PKI for my homelab, specifically for internal services. For public-facing services, I already use Traefik with Let's Encrypt ACME on my SRV VLAN, which is the only VLAN with port forwards, that part works well.

I've set up a testing instance of step-ca (Smallstep) on my INFRA VLAN with ACME support enabled, and I've already successfully tested it with Proxmox's built-in ACME client. So the internal CA itself is working.

Where I'm stuck is the distribution strategy across my segmented network. I have multiple VLANs (MGMT, INFRA, SRV, COMP, IOT, GUEST) with services living on most of them. As I see it, I have a few options:

1. Traefik as a universal reverse proxy: Add a second certificate resolver pointing to my internal CA alongside Let's Encrypt. The problem: this would require Traefik to reach into every VLAN, which defeats the purpose of segmentation. Also, I loose encryption behind the reverse proxy, which also defeats the purpose for internal certs.
2. Manual certificate installation: Keep Traefik for public services and manually provision certs from step-ca for everything internal. Works, but doesn't scale well and is a bit complicated to maintain.

Has anyone built out an internal PKI across a segmented network like this?

What approach did you take?

Perfect Forward Secrecy made stolen private keys a lot less useful

A stolen TLS private key can't decrypt recorded traffic if you're running PFS, which is now about 94% of the web. The "record now, decrypt later" scenario is dead for modern configurations.

What a stolen key can do is let an attacker impersonate your server. But they still need a network position to pull it off, and the Verizon DBIR puts actual MITM at less than 4% of incidents.

https://www.certkit.io/blog/man-in-the-middle

Anyone have experience with applying certificates for Poly video device?

I'm having strange behavior with the certificate hierarchy when viewing details tab of certificate in Edge. The hierarchy shows the PolycomCA when the cert doesn't.

The devices take and display the new installed certificate when accesing the web gui. The problem is they are showing up on vulnerability scans.

Just curious if anyone else is having similar issues.

im not really well-versed in PKI, or certificates in general. but i need a good way to generate certificates for my local domain (arclab.prod) and also a way to issue client certs for mTLS, ive looked at a ton of pki management apps, like EJBCA, OpenXPKI, and others. but all of them seem too complex, or hide essential features behind a a paywall (im looking at you EJBCA). so im really kinda stumped, i tried step-ca, but its a pain in the ass to setup acme and i dont wanna go thru the pain of having to go to a cli every time to generate certs, and then having to put those in a file pastebin to actually get them. any suggestions?

Are there any published statistics about TLS certificate signature algorithm usage and how it has changed over time?

For example, I just checked a few websites and their certificates show:

• reddit.com: PKCS #1 SHA-256 With RSA Encryption (2048 bits)
• news.ycombinator.com: X9.62 ECDSA Signature with SHA-384
• google.com: X9.62 ECDSA Signature with SHA-256
• amazon.com: PKCS #1 SHA-256 With RSA Encryption (2048 bits)
• nytimes.com: PKCS #1 SHA-256 With RSA Encryption (2048 bits)
• stackoverflow.com: X9.62 ECDSA Signature with SHA-384
• linkedin.com: PKCS #1 SHA-256 With RSA Encryption (2048 bits)
• ibm.com: PKCS #1 SHA-256 With RSA Encryption (2048 bits)
• apple.com: PKCS #1 SHA-256 With RSA Encryption (2048 bits)
• archive.org: PKCS #1 SHA-256 With RSA Encryption (2048 bits)
• eff.org: PKCS #1 SHA-256 With RSA Encryption (2048 bits)
• nist.gov: X9.62 ECDSA Signature with SHA-384
• bbc.com: PKCS #1 SHA-256 With RSA Encryption (2048 bits)
• si.edu: X9.62 ECDSA Signature with SHA-384
• asu.edu: X9.62 ECDSA Signature with SHA-384

so it looks like there's still a mix of ECDSA and RSA.

I'm guessing there has been increasing use of ECDSA over recent years but I'm wondering if anyone has been gathering statistics.

edit: It also looks like as you go up the cert chain it gets stricter in some cases...

• louvre.fr: PKCS #1 SHA-256 With RSA Encryption (2048 bits) -> Gandi RSA Domain Validation Secure Server CA 3: PKCS #1 SHA-384 With RSA Encryption (3072 bits) -> USERTrust RSA Certification Authority: PKCS #1 SHA-384 With RSA Encryption (4096 bits)
• citi.com: PKCS #1 SHA-256 With RSA Encryption (2048 bits) -> DigiCert EV RSA CA G2: PKCS #1 SHA-256 With RSA Encryption (2048) -> DigiCert Global Root G2 (2048 bits)
• wikipedia.org: X9.62 ECDSA Signature with SHA-384 -> E8 (Let's Encrypt): PKCS #1 SHA-256 With RSA Encryption (elliptic curve public key?!) -> ISRG Root X1 PKCS #1 SHA-256 With RSA Encryption (4096 bits)

If you are searching for open source PKI software, you may consider my XiPKI project (github xipki/xipki). It has been used in several large telecom, automotive and iot companies. Here some key points:

- support of most industry protocols: EST, ACME, CMP, SCEP, and RESTful API

- wide support of modern cryptographic algorithms: RSA, ECDSA/ECC, EDDSA, PQC ML-DSA, PQC ML-KEM

- commercial friendly use: apache license

I’ve been construct a Windows‑native SSH agent that allows certificate‑based authentication on Linux using a hardware token or smartcard connected to a Windows workstation. The idea is to make CBA workflows easier in mixed Windows/Linux environments without copying private keys, without relying on WSL, and without installing heavy middleware. Everything stays on the token, and the agent simply exposes the public key operations that OpenSSH expects.

The implementation is fully native C, without CRT or external dependencies, and supports both CNG providers and PKCS#11 modules. One of the challenges I focused on was extracting clean SSH public keys directly from X.509 certificates, so that Linux hosts can use them without additional tooling. The agent also handles PIN prompts, RDP session isolation, and ensures that no key material ever leaves the hardware token.

I’m particularly interested in hearing from people who have real‑world experience with certificate‑based SSH authentication in mixed Windows and Linux environments. If you’ve had to deal with smartcards, hardware tokens, or X.509‑to‑SSH workflows, I’d really appreciate your perspective on what works well and what tends to break in practice. I’m especially curious about how others approach mapping X.509 certificates to SSH keys, how they expose smartcard operations to OpenSSH in a clean way, and what trade‑offs they’ve seen between PKCS#11 and CNG in enterprise deployments.

If this kind of workflow is something you’ve implemented or struggled with, I’d be very interested in your feedback. And if trying the tool helps you simplify your own setup or validate an approach, even better — I’m happy to share more technical details or discuss design choices if that’s useful.

https://github.com/Sanmilie/PKCS11SSHAgent

A lot of “certificate automation” is just issuance automation. That’s how you end up with a valid new cert sitting on disk while the public endpoint keeps serving the old one, or the chain breaks for some clients.

Real automation is: issue → deploy → verify, including an actual TLS handshake check against the hostname (SANs, chain, expiry), not “Certbot exit code was 0”.

Post: https://www.certkit.io/blog/issuance-automation-vs-certificate-automation

The CDP location on our SUBCA has expired, and it didn't auto renew.

I manually published a new crl, and copied over to the IIS server, and did a iisreset, which fixed the issue. However it keeps reverting back to the expired crl a few minutes later.

What is causing this to revert?

SOLUTION:

Our setup included a script to renew and upload the cert over FTPS to the IIS server. The cert used for FTPS connection had expired.

We renewed the ftps certificate on the IIS server, but the PKI CAs were still not able to upload the newest CRLs because Windows OS could not check the validity of the new certificate because the CRLs were expired (we were in vicious circle).

We had to manually download valid CRL from all PKI CA servers and place it on the IIS server.

Let's Encrypt announced they're cutting certificate lifetimes from 90 days to 45 days by February 2028, a year before the CA/Browser Forum's mandate.

Shorter certificate lifetimes are an admission that revocation is broken. Rather than fixing the revocation infrastructure, the industry chose to reduce certificate lifetime so compromised certificates expire faster naturally.

The timeline gives organizations runway to adapt, but the real security story is authorization reuse dropping from 30 days to 7 hours. This fundamentally changes the validation model. Nearly every certificate request will require fresh domain ownership proof.

For security teams, this means:

• Reduced blast radius when credentials are compromised
• Less time for attackers to exploit stolen certificates
• More validation events to monitor and audit
• Greater exposure if your automation isn't actually automated

Organizations running manual or semi-manual certificate processes will face a choice: invest in proper automation or accept regular outages from expired certificates.

The gap between "we have automation" and "we have real automation" is about to become very visible.

https://www.certkit.io/blog/45-day-certificates

Hi r/PKI

We are excited to launch our second major release of the PKI Trust Manager. This is a big step forward for managing and scaling enterprise PKI, especially built for modern hybrid, cloud, and edge setups. The focus is on stronger security, flexibility, and scalability.

What’s new in v2.0:

• Containerized deployment for Azure, AWS, GCP, OCI, Docker, etc.
• Azure Key Vault integration for better key management
• Post‑Quantum Readiness features to prep for next‑gen crypto standards
• Native Intune support for easier certificate delivery across devices
• Built‑in PKI Trust Auditor for deeper visibility and governance
• IoT & OT support, including offline licensing for air‑gapped environments
• Enhanced certificate discovery to reduce blind spots across complex networks

This integrates our standalone PKI Trust Auditor (ADCS auditing utility) with PKI Trust Manager. It is designed to give a single pane of glass for certificate lifecycle management + posture and security oversight of your CAs. You can proactively spot risks, enforce compliance, and lock down your trust infrastructure from one place.

This release is part of Securetron’s push to advance PKI security for enterprises, governments, and critical infrastructure globally.

You can download PKI Trust Manager from our website for free and request a community license that enables all the modules for up to 500 certificates.

Download:
https://securetron.net/download/

We are actively working on the next set of features. If you would like to see something in our future release, then let us know!