Ecosyste.ms: Advisories

Security Advisories: GSA_kwCzR0hTQS0yY2NmLWZmcmotbTRxd84AAy6-

CSRF token fixation in fastify-passport

The CSRF protection enforced by the @fastify/csrf-protection library, when combined with @fastify/passport, can be bypassed by network and same-site attackers.

Details

fastify/csrf-protection implements the synchronizer token pattern (using plugins @fastify/session and @fastify/secure-session) by storing a random value used for CSRF token generation in the _csrf attribute of a user's session.

The @fastify/passport library does not clear the session object upon authentication, preserving the _csrf attribute between pre-login and authenticated sessions. Consequently, CSRF tokens generated before authentication are still valid. Network and same-site attackers can thus obtain a CSRF token for their pre-session, fixate that pre-session in the victim's browser via cookie tossing, and then perform a CSRF attack after the victim authenticates.

Fix

As a solution, newer versions of @fastify/passport include the configuration options

• clearSessionOnLogin (default: true) and
• clearSessionIgnoreFields (default: ['session'])

to clear all the session attributes by default, preserving those explicitly defined in clearSessionIgnoreFields.

Credits

• Pedro Adão (@pedromigueladao), Instituto Superior Técnico, University of Lisbon
• Marco Squarcina (@lavish), Security & Privacy Research Unit, TU Wien

Permalink: https://github.com/advisories/GHSA-2ccf-ffrj-m4qw
JSON: https://advisories.ecosyste.ms/api/v1/advisories/GSA_kwCzR0hTQS0yY2NmLWZmcmotbTRxd84AAy6-
Source: GitHub Advisory Database
Origin: Unspecified
Severity: Moderate
Classification: General
Published: about 1 year ago
Updated: 6 months ago

CVSS Score: 6.5
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

Identifiers: GHSA-2ccf-ffrj-m4qw, CVE-2023-29020
References:

• https://github.com/fastify/fastify-passport/security/advisories/GHSA-2ccf-ffrj-m4qw
• https://nvd.nist.gov/vuln/detail/CVE-2023-29020
• https://github.com/fastify/fastify-passport/commit/07c90feab9cba0dd4779e47cfb0717a7e2f01d3d
• https://cheatsheetseries.owasp.org/cheatsheets/Cross-Site_Request_Forgery_Prevention_Cheat_Sheet.html#synchronizer-token-pattern
• https://owasp.org/www-community/attacks/csrf
• https://github.com/advisories/GHSA-2ccf-ffrj-m4qw

Repository: https://github.com/fastify/fastify-passport
Blast Radius: 8.5

Affected Packages