{"id":"CVE-2026-92289","aliases":["DEBIAN-CVE-2026-92289","EUVD-2026-86489","GHSA-vw4x-93xp-f6f3","UBUNTU-CVE-2026-92289"],"status":"published","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","description":"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.","severity":{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical","assessor":"adp","from":"cve"},"epss":{"day":"2026-11-09","score":0.00537,"percentile":0.45537,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-1390"],"published":"2026-09-25T00:15:49Z","modified":"2026-10-28T02:30:36Z","fixes":[{"ecosystem":"Debian:13","package":"lemonldap-ng","fixed_in":["2.21.2+ds-1+deb13u4"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"lemonldap-ng","fixed_in":["2.23.4+ds-1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:13","package":"lemonldap-ng","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.21.2+ds-1+deb13u4"}]}],"versions":["2.21.2+ds-1","2.21.2+ds-1+deb13u1","2.21.2+ds-1+deb13u2","2.21.2+ds-1+deb13u3"]},{"source":"osv","ecosystem":"Debian:14","package":"lemonldap-ng","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.23.4+ds-1"}]}],"versions":["2.21.2+ds-1","2.21.2+ds-2","2.21.3+ds-1","2.21.3+ds-1~bpo12+1","2.21.3+ds-1~bpo13+1","2.22.0+ds-1","2.22.0+ds-2","2.22.0+ds-2~bpo13+1","2.22.1+ds-1","2.22.1+ds-1~bpo13+1","2.22.2+ds-1","2.22.2+ds-1~bpo13+1","2.22.3+ds-1","2.22.3+ds-1~bpo13+1","2.23.0+ds-1","2.23.0+ds-2","2.23.0+ds-3","2.23.0+ds-3~bpo13+1","2.23.0+ds-4","2.23.1+ds-1","2.23.2+ds-1","2.23.2+ds-1~bpo13+1","2.23.2+ds-2","2.23.3+ds-1"]},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"lemonldap-ng","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.3.3-1","1.4.6-1","1.4.6-2","1.4.6-3"]},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"lemonldap-ng","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.9.10-1","1.9.13-2","1.9.14-1","1.9.15-1","1.9.16-2"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"lemonldap-ng","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.0.5+ds-2","2.0.6+ds-2","2.0.7+ds-2"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"lemonldap-ng","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.0.11+ds-4","2.0.13+ds-3","2.0.13+ds-3ubuntu1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"lemonldap-ng","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.16.2+ds-1","2.17.1+ds-1","2.17.2+ds-1","2.17.2+ds-2","2.18.1+ds-1","2.18.2+ds-1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"lemonldap-ng","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.22.2+ds-1","2.22.3+ds-1","2.23.0+ds-3","2.23.0+ds-4","2.23.2+ds-1","2.23.2+ds-2","2.23.3+ds-1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"lemonldap-ng","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.21.0+ds-3","2.22.0+ds-2","2.22.1+ds-1","2.22.2+ds-1"]}],"references":[{"url":"https://gitlab.ow2.org/lemonldap-ng/lemonldap-ng/-/work_items/3719","tags":["issue-tracking","exploit","report"]},{"url":"https://gitlab.ow2.org/lemonldap-ng/lemonldap-ng/-/releases/v2.23.4","tags":["release-notes","advisory"]},{"url":"http://www.openwall.com/lists/oss-security/2026/09/25/2","tags":["web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-92289","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-vw4x-93xp-f6f3"},{"url":"https://cpan.org/modules","tags":["web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/92xxx/CVE-2026-92289.json","tags":["advisory"]},{"url":"https://gitlab.ow2.org/lemonldap-ng/lemonldap-ng","tags":["package"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-92289","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-92289","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-92289","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-92289","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","description":"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.","status":"published","published":"2026-09-25T00:15:49.826Z","modified":"2026-09-26T22:29:08.052Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical","assessor":"adp"}],"cwes":["CWE-1390"],"updated_at":"2026-11-02T13:48:24.536396Z"}],"euvd":[{"id":"EUVD-2026-86489","description":"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.","status":"published","published":"2026-09-25T00:15:49Z","modified":"2026-09-26T22:29:08Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical"}],"updated_at":"2026-11-02T17:27:54.622662Z"}],"ghsa":[{"id":"GHSA-vw4x-93xp-f6f3","title":"Lemonldap::NG::Portal versions from 2.23.0 before 2.23.4 for Perl allow a PKCE bypass for public...","description":"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.","status":"published","published":"2026-09-25T03:31:00Z","modified":"2026-09-27T00:32:20Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical"}],"cwes":["CWE-1390"],"updated_at":"2026-11-02T15:12:30.689958Z"}],"nvd":[{"id":"CVE-2026-92289","description":"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.","status":"published","published":"2026-09-25T01:16:48.943Z","modified":"2026-09-26T23:16:38.897Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical","assessor":"secondary"}],"cwes":["CWE-1390"],"updated_at":"2026-11-02T14:12:51.388161Z"}],"osv":[{"id":"CVE-2026-92289","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","description":"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.","status":"published","published":"2026-09-25T00:15:49.826Z","modified":"2026-10-28T02:30:36.798155008Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical"}],"cwes":["CWE-1390"],"updated_at":"2026-11-02T15:45:20.269367Z"},{"id":"DEBIAN-CVE-2026-92289","description":"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.","status":"published","published":"2026-09-25T01:16:48.943Z","modified":"2026-10-18T04:00:09.027978174Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical"}],"updated_at":"2026-11-02T15:46:06.410207Z"},{"id":"UBUNTU-CVE-2026-92289","description":"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.","status":"published","published":"2026-09-25T01:16:00Z","modified":"2026-10-17T13:01:17.593956731Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical"}],"updated_at":"2026-11-02T16:57:40.980117Z"}]}}