Описание
The FIDO2/Webauthn Support for PHP library allows enumeration of valid usernames
Summary
The ProfileBasedRequestOptionsBuilder method returns allowedCredentials without any credentials if no username was found.
Details
When WebAuthn is used as the first or only authentication method, an attacker can enumerate usernames based on the absence of the allowedCredentials property in the assertion options response. This allows enumeration of valid or invalid usernames.
Proposal how to resolve it:
PoC
curl https://example.com/assertion/options
-H 'content-type: application/json'
--data-raw '{"username":"NotMeRandomUsername123"}'
Impact
By knowing which usernames are valid, attackers can focus their efforts on a smaller set of potential targets, increasing the efficiency and likelihood of successful attacks.
Ссылки
- https://github.com/web-auth/webauthn-framework/security/advisories/GHSA-875x-g8p7-5w27
- https://nvd.nist.gov/vuln/detail/CVE-2024-39912
- https://github.com/web-auth/webauthn-framework/commit/64de11f6cddc71e56c76e0cc4573bf94d02be045
- https://github.com/web-auth/webauthn-framework/commit/a9d1352897fba552e659e1445a771dec2d4ed05a
- https://github.com/web-auth/webauthn-lib/commit/b6798de27cdedd8681fe4c9b13ace0ff2456d18b
Пакеты
web-auth/webauthn-lib
>= 4.5.0, < 4.9.0
4.9.0
web-auth/webauthn-framework
>= 4.5.0, < 4.9.0
4.9.0
Связанные уязвимости
web-auth/webauthn-lib is an open source set of PHP libraries and a Symfony bundle to allow developers to integrate that authentication mechanism into their web applications. The ProfileBasedRequestOptionsBuilder method returns allowedCredentials without any credentials if no username was found. When WebAuthn is used as the first or only authentication method, an attacker can enumerate usernames based on the absence of the `allowedCredentials` property in the assertion options response. This allows enumeration of valid or invalid usernames. By knowing which usernames are valid, attackers can focus their efforts on a smaller set of potential targets, increasing the efficiency and likelihood of successful attacks. This issue has been addressed in version 4.9.0 and all users are advised to upgrade. There are no known workarounds for this vulnerability.
Уязвимость метода ProfileBasedRequestOptionsBuilder библиотеки аутентификации в веб-приложениях webauthn-lib, позволяющая нарушителю получить несанкционированный доступ к защищаемой информации