{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-92289","assignerOrgId":"9b29abf9-4ab0-4765-b253-1875cd9b441e","state":"PUBLISHED","assignerShortName":"CPANSec","dateReserved":"2026-09-15T23:43:48.309Z","datePublished":"2026-09-25T00:15:49.826Z","dateUpdated":"2026-09-26T22:29:08.052Z"},"containers":{"cna":{"affected":[{"collectionURL":"https://cpan.org/modules","defaultStatus":"unaffected","modules":["Lemonldap::NG::Portal"],"packageName":"Lemonldap-NG-Portal","packageURL":"pkg:cpan/Lemonldap-NG-Portal","programFiles":["lib/Lemonldap/NG/Portal/Lib/OpenIDConnect.pm","lib/Lemonldap/NG/Portal/Issuer/OpenIDConnect.pm"],"programRoutines":[{"name":"Lemonldap::NG::Portal::Lib::OpenIDConnect::checkEndPointAuthenticationCredentials"},{"name":"Lemonldap::NG::Portal::Issuer::OpenIDConnect::token"}],"repo":"https://gitlab.ow2.org/lemonldap-ng/lemonldap-ng","versions":[{"lessThan":"2.23.4","status":"affected","version":"2.23.0","versionType":"custom"}]}],"descriptions":[{"lang":"en","value":"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.\n\nWith 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.\n\nAn 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."}],"problemTypes":[{"descriptions":[{"cweId":"CWE-1390","description":"CWE-1390 Weak Authentication","lang":"en","type":"CWE"}]}],"providerMetadata":{"orgId":"9b29abf9-4ab0-4765-b253-1875cd9b441e","shortName":"CPANSec","dateUpdated":"2026-09-25T00:15:49.826Z"},"references":[{"tags":["issue-tracking"],"url":"https://gitlab.ow2.org/lemonldap-ng/lemonldap-ng/-/work_items/3719"},{"tags":["release-notes"],"url":"https://gitlab.ow2.org/lemonldap-ng/lemonldap-ng/-/releases/v2.23.4"}],"solutions":[{"lang":"en","value":"Upgrade to Lemonldap-NG-Portal 2.23.4 or later."}],"source":{"discovery":"UNKNOWN"},"title":"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","workarounds":[{"lang":"en","value":"For deployments that cannot upgrade to 2.23.4, set RequirePKCE to 1 on public Relying Parties so that a code challenge is always required. Relying Parties created through dynamic registration are always in \"PKCE or secret\" mode, so that endpoint has to be disabled as well."}],"x_generator":{"engine":"cpansec-cna-tool 0.1"}},"adp":[{"title":"CVE Program Container","references":[{"url":"http://www.openwall.com/lists/oss-security/2026/09/25/2"}],"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2026-09-25T02:10:01.838Z"}},{"references":[{"url":"https://gitlab.ow2.org/lemonldap-ng/lemonldap-ng/-/work_items/3719","tags":["exploit"]}],"metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":9.1,"attackVector":"NETWORK","baseSeverity":"CRITICAL","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","integrityImpact":"HIGH","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"NONE","privilegesRequired":"NONE","confidentialityImpact":"HIGH"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-09-25T15:38:54.575555Z","id":"CVE-2026-92289","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-09-26T22:29:08.052Z"}}]}}