Description (CNA)
Lemonldap::NG::Portal versions from 2.23.0 before 2.23.4 for Perl allow a PKCE bypass for public Relying Parties in "PKCE or secret" mode because checkEndPointAuthenticationCredentials does not verify the client secret. With oidcRPMetaDataOptionsRequirePKCE set to 2, the authorization endpoint issues a code even when the request carries no code_challenge, and token() admits the exchange as long as a challenge was stored or an authentication method was returned for the caller. checkEndPointAuthenticationCredentials() skips the secret comparison for a Relying Party marked public and still returns the method deduced from the request, so any Basic or form credential satisfies the secret branch. validatePKCEChallenge() then passes, because neither a challenge nor a verifier is present. An attacker who intercepts an authorization code issued to a public Relying Party can exchange it for the user's access, ID and refresh tokens by replaying the client_id with an arbitrary secret, which is the attack PKCE prevents. Dynamic client registration creates every Relying Party in this mode.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Not supplied / Not supplied | affected 2.23.0 before 2.23.4 |
CWE
CWE-1390
References
- https://gitlab.ow2.org/lemonldap-ng/lemonldap-ng/-/work_items/3719
- https://gitlab.ow2.org/lemonldap-ng/lemonldap-ng/-/releases/v2.23.4
ADP enrichment
No English description supplied.
No English description supplied.