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
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.
CVE-2026-92289
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-92289
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://gitlab.ow2.org/lemonldap-ng/lemonldap-ng",
"modules": [
"Lemonldap::NG::Portal"
],
"versions": [
{
"status": "affected",
"version": "2.23.0",
"lessThan": "2.23.4",
"versionType": "custom"
}
],
"packageURL": "pkg:cpan/Lemonldap-NG-Portal",
"packageName": "Lemonldap-NG-Portal",
"programFiles": [
"lib/Lemonldap/NG/Portal/Lib/OpenIDConnect.pm",
"lib/Lemonldap/NG/Portal/Issuer/OpenIDConnect.pm"
],
"collectionURL": "https://cpan.org/modules",
"defaultStatus": "unaffected",
"programRoutines": [
{
"name": "Lemonldap::NG::Portal::Lib::OpenIDConnect::checkEndPointAuthenticationCredentials"
},
{
"name": "Lemonldap::NG::Portal::Issuer::OpenIDConnect::token"
}
]
}
]- Related CVEs
- CVE-2026-92289
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #2372 · Revision 1
- Added to Heist Feed
- Publisher date