Skip to main content
banner image
venafi logo

Let’s Encrypt is Revoking SSL Certificates Massively—Again

Let’s Encrypt is Revoking SSL Certificates Massively—Again

let’s-encrypt-is-revoking-ssl-certificates-massively-again
January 26, 2022 | Brooke Crothers

Let's Encrypt has notified subscribers that on 28 January 2022 it will revoke certain certificates issued in the last 90 days, according to a staff member’s response on a Let’s Encrypt forum.  Let’s Encrypt, a non-profit certificate authority run by Internet Security Research Group (ISRG), said that not everyone will be necessarily notified, and they are working to provide a way for subscribers to see if they are affected. This is another example of why PKI teams may be inadvertently placed in a situation where they need to quickly and automatically replace any individual Certificate Authority (CA), certificate or groups of certificates. Unfortunately, the vast majority of organizations don’t have the visibility or automation required to do this.

Are Your Machine Identities Crypto Agile? Find Out with Our Buyer’s Guide!

The revocation only affects certificates issued and validated with the TLS-ALPN-01 “challenge,” according to Let’s Encrypt, which it describes as a way for its servers to validate control of the domain names in that certificate. “When you get a certificate from Let’s Encrypt, our servers validate that you control the domain names in that certificate using ‘challenges,’ as defined by the ACME standard,” according to Let’s Encrypt.

The news was first reported by Bleeping Computer.

The Let’s Encrypt staffer goes on to say that “all successful issuance in last 90 days with the TLS-ALPN-01 challenge are affected and will be revoked. If you only use that challenge, you should force renew all of your certificates. If you only use that challenge for some domains but are having trouble determining which ones based on the account, it is safe to force renew all your certificates.”

This follows an incident in February 2020 when Let’s Encrypt revoked millions of certificates in response to a bug in its Certificate Authority Authorization (CAA) code.

Let’s Encrypt popularity explodes

Let’s Encrypt has become extremely popular with developers. That popularity makes an incident like this significant.

“Let’s Encrypt has boomed in popularity with developers over the last few years, as it gives developers a quick, free and easy way to issue TLS machine identities for all manner of critical web services—from websites to customer applications,” says Kevin Bocek, VP Security and Threat Intelligence at Venafi.

Bocek points to a recent crawler report from Venafi and security expert Scott Helme showing that Let’s Encrypt now has millions of active certificates in use, with 28% of the top 1 million sites making use of it.

“This means that when Let’s Encrypt suddenly has to revoke millions of certificates—as is the case right now—it can create major upheaval, putting critical services at risk of outage, with organizations having to quickly find and reissue potentially tens of thousands of machine identities within just two or three days,” Bocek says.

Venafi solution

Doing this manually is almost impossible and highly prone to potentially costly errors, according to Bocek.  Add to that the fact that businesses could have tens of thousands of machine identities that they aren’t even aware of.

“To protect against events such as these, which are becoming increasingly common, security teams should be automating machine identity management. By doing so, they can avoid manual rotation, replacement and revocation of all machines,” Bocek says.

Customers of Venafi’s machine identity management platform, regardless of what datacenter product or cloud product they are using, are protected by the agility Venafi offers, says Jing Xie, Ecosystem Manager of Business Development at Venafi.

“The Venafi Platform offers complete visibility and inventory of all Let’s Encrypt issued certificates. With a few clicks, it helps replace all affected certificates with newly issued and secure ones without service disruption,” Xie says.

This is not the first or last time that an incident will cause domain users to scramble to recover. Venafi has outlined the long history of CA errors that impacted the security of machine identities such as TLS certificates. 

Related posts

Like this blog? We think you will love this.
managed-pki
Featured Blog

Exposed TLS Certificates Force PKI Lead to Quit: How Badly Managed PKI Poses Serious Risk [Case Study]

'I'm out of here' — PKI lead  That’s th

Read More
Subscribe to our Weekly Blog Updates!

Join thousands of other security professionals

Get top blogs delivered to your inbox every week

Subscribe Now

See Popular Tags

You might also like

TLS Machine Identity Management for Dummies
eBook

TLS Machine Identity Management for Dummies

Certificate-Related Outages Continue to Plague Organizations
White Paper

CIO Study: Certificate-Related Outages Continue to Plague Organizations

About the author

Brooke Crothers
Brooke Crothers
Read Posts by Author
get-started-overlay close-overlay cross icon
get-started-overlay close-overlay cross icon
Venafi Risk assessment Form Image

Sign up for Venafi Cloud


Venafi Cloud manages and protects certificates



* Please fill in this field Please enter valid email address
* Please fill in this field Password must be
At least 8 characters long
At least one digit
At last one lowercase letter
At least one uppercase letter
At least one special character
(@%+^!#$?:,(){}[]~`-_)
* Please fill in this field
* Please fill in this field
* Please fill in this field
*

End User License Agreement needs to be viewed and accepted



Already have an account? Login Here

×
get-started-overlay close-overlay cross icon

How can we help you?

Thank you!

Venafi will reach out to you within 24 hours. If you need an immediate answer please use our chat to get a live person.

In the meantime, please explore more of our solutions

Explore Solutions

learn more

Email Us a Question

learn more

Chat With Us

learn more