Before redirecting to the identity provider, extractFormInfo() creates the state session with the positional call `getApacheSession( undef, 1, 0, 'GitHubState' )`. getApacheSession() takes a session id followed by a named argument hash, so the trailing arguments become that hash, `kind` defaults to SSO, and the state is written to the global session storage as a regular SSO session. Its identifier is handed to the unauthenticated visitor as the state parameter of the redirection URL.
Any visitor who reaches the GitHub or LinkedIn endpoint can replay that identifier as a session cookie and obtain a valid SSO session without authenticating. The session holds neither _user nor authenticationLevel, which the shipped bootstrap configuration accepts because it grants virtual hosts a "default => accept" access rule; deployments whose rules test the user or require an authentication level are less exposed. Only configurations with the GitHub or LinkedIn authentication module enabled are affected.
Analysis and contextual insights are available on OpenCVE Cloud.
Vendor Solution
Upgrade to Lemonldap-NG-Portal 2.16.9, 2.21.5 or 2.23.3 or later. Only 2.23.3 is on CPAN; the 2.16.9 and 2.21.5 LTS releases are available from https://lemonldap-ng.org/download.html.
Vendor Workaround
For deployments that cannot upgrade, disable the GitHub and LinkedIn authentication modules.
Tracking
Sign in to view the affected projects.
| Source | ID | Title |
|---|---|---|
Debian DSA |
DSA-6434-1 | lemonldap-ng security update |
Sun, 16 Aug 2026 13:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Lemonldap::NG::Portal versions from 2.0.0 before 2.16.9, from 2.17.0 before 2.21.5, from 2.22.0 before 2.23.3 for Perl allow authentication bypass via an OAuth2 state parameter stored as an SSO session in the GitHub and LinkedIn backends. Before redirecting to the identity provider, extractFormInfo() creates the state session with the positional call `getApacheSession( undef, 1, 0, 'GitHubState' )`. getApacheSession() takes a session id followed by a named argument hash, so the trailing arguments become that hash, `kind` defaults to SSO, and the state is written to the global session storage as a regular SSO session. Its identifier is handed to the unauthenticated visitor as the state parameter of the redirection URL. Any visitor who reaches the GitHub or LinkedIn endpoint can replay that identifier as a session cookie and obtain a valid SSO session without authenticating. The session holds neither _user nor authenticationLevel, which the shipped bootstrap configuration accepts because it grants virtual hosts a "default => accept" access rule; deployments whose rules test the user or require an authentication level are less exposed. Only configurations with the GitHub or LinkedIn authentication module enabled are affected. | |
| Title | Lemonldap::NG::Portal versions from 2.0.0 before 2.16.9, from 2.17.0 before 2.21.5, from 2.22.0 before 2.23.3 for Perl allow authentication bypass via an OAuth2 state parameter stored as an SSO session in the GitHub and LinkedIn backends | |
| Weaknesses | CWE-305 CWE-628 |
|
| References |
|
Subscriptions
No data.
Status: PUBLISHED
Assigner: CPANSec
Published:
Updated: 2026-08-16T13:22:34.084Z
Reserved: 2026-08-08T14:18:36.846Z
Link: CVE-2026-19349
No data.
Status : Received
Published: 2026-08-16T14:16:54.720
Modified: 2026-08-16T14:16:54.720
Link: CVE-2026-19349
No data.
OpenCVE Enrichment
No data.
Debian DSA