InCommon Root/Intermediary Certificates:

• "ADDTrust External CA Root"  OR
• "USERTrust Intermediate Certificate"

issued by:

• "USERTrust RSA Certification Authority"  OR
• "InCommon Sectigo Certificate Service"

that have not been properly updated will expire on May 30, 2020 at 5:48AM CST.   The result will be application failure or secure communications failure.  

Please utilize the following replacement certificates (attached to this KB article) to update your application certificate bundle (store, trust, or library) to ensure continued secure operation.

• USERTrust-RSA-Certificate.txt (expires January 18, 2038)
• InCommon-RSA-Server-CA-Certificate.txt  (expires October 5, 2024)

Certificates are PEM encoded (base64 encoded) and are plain text.   Once you download the file, you can rename the file extension from "txt" to "cer" or "crt", depending on what your operating system or application requires.   In some cases you can just copy and paste the contents of the files into the appropriate locations.   Please consult application and/or operating system documentation for instructions on verifying and/or updating the certificate chain.