Headline
GHSA-g8x5-p9qc-cf95: @fastify/oauth2 vulnerable to Cross Site Request Forgery due to reused Oauth2 state
Impact
All versions of @fastify/oauth2 used a statically generated state parameter at startup time and were used across all requests for all users.
The purpose of the Oauth2 state parameter is to prevent Cross-Site-Request-Forgery attacks. As such, it should be unique per user and should be connected to the user’s session in some way that will allow the server to validate it.
Patches
v7.2.0 changes the default behavior to store the state in a cookie with the http-only and same-site=lax attributes set. The state is now by default generated for every user.
Note that this contains a breaking change in the checkStateFunction function, which now accepts the full Request object.
Workarounds
There are no known workarounds.
References
Package
npm @fastify/oauth2 (npm)
Affected versions
< 7.2.0
Patched versions
7.2.0
Description
Impact
All versions of @fastify/oauth2 used a statically generated state parameter at startup time and were used across all requests for all users.
The purpose of the Oauth2 state parameter is to prevent Cross-Site-Request-Forgery attacks. As such, it should be unique per user and should be connected to the user’s session in some way that will allow the server to validate it.
Patches
v7.2.0 changes the default behavior to store the state in a cookie with the http-only and same-site=lax attributes set. The state is now by default generated for every user.
Note that this contains a breaking change in the checkStateFunction function, which now accepts the full Request object.
Workarounds
There are no known workarounds.
References
- Prevent Attacks and Redirect Users with OAuth 2.0 State Parameters
References
- GHSA-g8x5-p9qc-cf95
- https://nvd.nist.gov/vuln/detail/CVE-2023-35935
- fastify/fastify-oauth2@bff756b
- https://auth0.com/docs/secure/attack-protection/state-parameters
- https://github.com/fastify/fastify-oauth2/releases/tag/v7.2.0
mcollina published to fastify/fastify-oauth2
Jul 3, 2023
Published to the GitHub Advisory Database
Jul 5, 2023
Reviewed
Jul 5, 2023
Last updated
Jul 5, 2023
Related news
@fastify/oauth2, a wrapper around the `simple-oauth2` library, is vulnerable to cross site request forgery (CSRF) prior to version 7.2.0.. All versions of @fastify/oauth2 used a statically generated `state` parameter at startup time and were used across all requests for all users. The purpose of the Oauth2 `state` parameter is to prevent CSRF attacks. As such, it should be unique per user and should be connected to the user's session in some way that will allow the server to validate it. Version 7.2.0 changes the default behavior to store the `state` in a cookie with the `http-only` and `same-site=lax` attributes set. The state is now by default generated for every user. Note that this contains a breaking change in the `checkStateFunction` function, which now accepts the full `Request` object. There are no known workarounds for the issue.