CSRF in Fastify Fastify-Passport
CVE-2023-29020
@fastify/passport is a port of passport authentication library for the Fastify ecosystem. The CSRF (Cross-Site Request Forger) protection enforced by the `@fastify/csrf-protection` library, when combined with `@fastify/passport` in affected versions, can be bypassed by network and same-site attackers. `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. As a solution, newer versions of `@fastify/passport` include the configuration options: `clearSessionOnLogin (default: true)` and `clearSessionIgnoreFields (default: ['passport', 'session'])` to clear all the session attributes by default, preserving those explicitly defined in `clearSessionIgnoreFields`.
Vulnerability class: CSRF (Cross-Site Request Forgery)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N.
EPSS exploit prediction
EPSS: 0.004 (29.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 29.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Fastify Fastify-Passport — versions < 1.1.0, >= 2.0.0, < 2.3.0
- Fastify Passport
Weakness classification (CWE)
References
- github.com/fastify/fastify-passport/security/advisories/GHSA-2ccf-ffrj-m4qw (Vendor Advisory)
- github.com/fastify/fastify-passport/commit/07c90feab9cba0dd4779e47cfb0717a7e2f0… (Patch)
- cheatsheetseries.owasp.org/cheatsheets/Cross-Site_Request_Forgery_Prevention_Ch… (Technical Description)
- owasp.org/www-community/attacks/csrf (Technical Description)
Frequently asked questions
- What is CVE-2023-29020?
- CVE-2023-29020 is a medium-severity vulnerability in Fastify Fastify-Passport, classified under Cross-Site Request Forgery (CSRF). CVSS score: 6.5/10. Published 2023-04-21.
- How severe is CVE-2023-29020?
- Medium severity. CVSS v3 base score is 6.5 out of 10.