DRUPAL-CONTRIB-2026-284: Composer/drupal/oauth_login_oauth2 vulnerability

Q: Which deployments are exposed to this issue?

Sites using the OAuth Login OAuth2 module with an OAuth 2.0 or OpenID Connect identity provider configured are the relevant population. Exploitation also depends on the configured provider allowing the attacker to have an account and control at least one returned attribute, such as a username.

Q: What must an attacker be able to do to exploit the issue?

The attacker needs an account at an identity provider that the site is configured to use. They must be able to set the value of at least one attribute returned by that provider and know the email address of an existing site user.

Published Oct 28, 2026

Updated

This module enables you to log in to your Drupal site using any OAuth 2.0 or OpenID Connect compliant identity provider.

The module doesn't sufficiently check access on a configuration route, or check whether the identity provider has verified the email address it returns. Together, these let an attacker log in as any existing user whose email address they know.

This vulnerability is mitigated by the fact that an attacker must have an account with an identity provider the site is configured to use. They must also be able to set the value of at least one attribute that provider returns, such as a username.

Affected Software

1 affected componentFixes available

composer/drupal/oauth_login_oauth2<3.1.1

3.1.1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade composer/drupal/oauth_login_oauth2 to a version that resolves this vulnerability.
Fixed in 3.1.1

Event History

Oct 28, 2026

Advisory Published

via OSV·05:35 PM

Data Sourced

via OSV·05:35 PM

DescriptionAffected Software

Frequently Asked Questions

Which deployments are exposed to this issue?

Sites using the OAuth Login OAuth2 module with an OAuth 2.0 or OpenID Connect identity provider configured are the relevant population. Exploitation also depends on the configured provider allowing the attacker to have an account and control at least one returned attribute, such as a username.

What must an attacker be able to do to exploit the issue?

The attacker needs an account at an identity provider that the site is configured to use. They must be able to set the value of at least one attribute returned by that provider and know the email address of an existing site user.

DRUPAL-CONTRIB-2026-284: Composer/drupal/oauth_login_oauth2 vulnerability

Affected Software

Remediation

Event History

Frequently Asked Questions

Which deployments are exposed to this issue?

What must an attacker be able to do to exploit the issue?

Company

Resources

Contact

Frequently Asked Questions

Which deployments are exposed to this issue?

What must an attacker be able to do to exploit the issue?