Impact What kind of vulnerability is it? Who is impacted?

Original Report:

The Oauth1/2 "state" and OpenID Connect "nonce" is vulnerable for a "timing attack" since it's compared via regular string comparison (instead of Yii::$app->getSecurity()->compareString()).

Affected Code:

1. OAuth 1 "state"

https://github.com/yiisoft/yii2-authclient/blob/0d1c3880f4d79e20aa1d77c012650b54e69695ff/src/OAuth1.php#L158

3. OAuth 2 "state" https://github.com/yiisoft/yii2-authclient/blob/0d1c3880f4d79e20aa1d77c012650b54e69695ff/src/OAuth2.php#L121

4. OpenID Connect "nonce" https://github.com/yiisoft/yii2-authclient/blob/0d1c3880f4d79e20aa1d77c012650b54e69695ff/src/OpenIdConnect.php#L420

Patches Has the problem been patched? What versions should users upgrade to?

TBD: Replace strcmp with Yii::$app->getSecurity()->compareString()).

Workarounds Is there a way for users to fix or remediate the vulnerability without upgrading?

not as far as I see.

References Are there any links users can visit to find out more?

Impact What kind of vulnerability is it? Who is impacted?

Original Report:

The Oauth2 PKCE implementation is vulnerable in 2 ways: 1. The authCodeVerifier should be removed after usage (similar to 'authState') 2. There is a risk for a "downgrade attack" if PKCE is being relied on for CSRF protection.

Patches Has the problem been patched? What versions should users upgrade to?

2.2.15

Workarounds Is there a way for users to fix or remediate the vulnerability without upgrading?

not known yet.

References Are there any links users can visit to find out more?