See https://status.yubico.com/2018/11/26/deprecating-yubicloud-v1-protocol-plain-text-requests-and-old-tls-versions/

Endpoints

YubiCloud endpoints are available at the following addresses:

https://api.yubico.com/wsapi/2.0/verify?id=&otp=&nonce=
https://api2.yubico.com/wsapi/2.0/verify?id=&otp=&nonce=
https://api3.yubico.com/wsapi/2.0/verify?id=&otp=&nonce=
https://api4.yubico.com/wsapi/2.0/verify?id=&otp=&nonce=
https://api5.yubico.com/wsapi/2.0/verify?id=&otp=&nonce=

To ensure high-availability, configure your client to simultaneously issue requests to all five addresses and accept the first successful reply.

In a future YubiCloud protocol version, this client-side complexity will be replaced with a single highly-available endpoint.

For TYPO3 11 we can use YubikeyAuthService from ext:mfa_yubikey, which uses psr/http-client and psr/http-factory for requests

Login-Template is not rendered due to missing variable.

TYPO3 12
PHP 8.x
sf_yubikey 5.0.2

Relying on this function is highly discouraged.

PHP Runtime Deprecation Notice: Function utf8_encode() is deprecated in
typo3conf\ext\sf_yubikey\Classes\Service\YubikeyService.php line 80

https://www.php.net/manual/en/function.utf8-encode.php

This should be 9.5.0 - ...

• Wrong title

• Convert to REsT
• Describe new features

Introduce namespaces and remove all TYPO3 4.5 related code

Is the current version compatible with TYPO3 8 and/or do you plan to add this?

In TYPO3 6.2 the login form is not shown due to changes $TBE_STYLES configuration

$GLOBALS['TYPO3_CONF_VARS']['SYS']['curlProxyServer'] has been removed in TYPO3 9.5 (https://forge.typo3.org/issues/70056)

The new setting should also be respected if set

• Problems with login-screen after update -> Remove Cache Files

Add TYPO3 6.0 login Template

Starting on December 10th, 2018, support for YubiCloud v1 protocol, plain-text requests and old TLS protocols & ciphers will be deprecated.

https://status.yubico.com/2018/11/26/deprecating-yubicloud-v1-protocol-plain-text-requests-and-old-tls-versions/

Detailed timeline
2018-11-26
Publication date of this blog post.

2018-12-10
Approximately 50% of traffic matching criteria is rejected with an HTTP 410 response status.

2019-02-04
100% traffic matching criteria is rejected with an HTTP 410 response status.

2019-03-04
– Requests for /wsapi/verify, /wsapi/1.0/verify and /wsapi/1.1/verify return an HTTP 404 response status.
– http:// traffic is rejected on the firewall level without any HTTP response code or redirects.
– TLS handshake requires TLS1.2 and ECDHE or AES ciphersuites.

• Bundled PEAR class not available any more
• No support for YubiKey PEAR extension on server
• Fix link on page "What does it do"
• Wrong title

When ext:yubikey is installed, the password recovery link for the TYPO3 backend is not shown