Android 11 and lower stopped working with CertPathValidatorException

[hostmaster23]

Describe the issue you are having:
After 17th of May, our Android application stopped working on devices with Android 11 and older
with NetworkErrorException: java.security.cert.CertPathValidatorException: Trust anchor for certification path not found. error

What steps have you taken to resolve the issue?

we moved our domain to by-pass

Was the site working with SSL prior to adding it to Cloudflare?
was working correctly until 17th of May

[v.zhuravlyov]

Certificate Authority - Google Trust?

[hostmaster23]

yes
Organization: Google Trust Services LLC
Valid from October 4, 2022 to September 29, 2027

[marsha]

Facing similar issue with Google cert too…
Apps with Android < 8 are affected.
Opened a ticket and cloudflare said that cert with google root is no longer used for universal SSL.
Disabled and enabled universal SSL does not solve the issue tho. Had to use this API to change our cert to lets encrypt:

curl -X PATCH "https://api.cloudflare.com/client/v4/zones/[zone-api]/ssl/universal/settings" \
     -H "X-Auth-Email: [email]" \
     -H "X-Auth-Key: [global api key]" \
     -H "Content-Type: application/json" \
     --data '{"certificate_authority":"lets_encrypt"}'

But, I don’t find it documented, only found it in community…so you may use it very carefully if you want to do it.

[marsha]

*android < 9
sorry typo