Fastify
CVE-2023-29020
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V3 - Web Frontend Security Anti-CSRF tokens, SameSite cookies
MITRE ATT&CK
1 technique across 1 tactic: Initial Access The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 6.5 (MEDIUM). Attack characteristics: network attack vector, low complexity, no privileges required, user interaction required. |
| Exploit ScenarioDerived | A remote attacker could trick authenticated users into performing unintended actions by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
@fastify/passport is a port of passport authentication library for the Fastify ecosystem. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Cross-Site Request Forgery (CSRF) vulnerability could allow attackers to trick authenticated users into performing unintended actions.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Implement anti-CSRF tokens, validate Origin/Referer headers, use SameSite cookie attribute.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in npm
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Cross-Site Request Forgery (CSRF) (CWE-352), which allows attackers to trick authenticated users into performing unintended actions. @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. Affected products include: Fastify Passport.
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Severity by source
AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
@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.
Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Cross-Site Request Forgery exploits the automatic credential inclusion behavior of web browsers.
Affected Products (CPE)NVD
All versions of @fastify/oauth2 used a statically generated state parameter at startup time and were used across all req
A redirect vulnerability in the `fastify-static` module version >= 4.2.4 and < 4.4.1 allows remote attackers to redirect
Fastify is a fast and low overhead web framework, for Node.js. Rated high severity (CVSS 7.5), this vulnerability is rem
Prototype pollution vulnerability in fastify-multipart < 1.0.5 allows an attacker to crash fastify applications parsing
Fastify node module before 0.38.0 is vulnerable to a denial-of-service attack by sending a request with "Content-Type: a
A denial of service vulnerability exists in Fastify v2.14.1 and v3.0.0-rc.4 that allows a malicious user to trigger reso
A redirect vulnerability in the fastify-static module version < 4.2.4 allows remote attackers to redirect users to arbit
Authorization bypass in the @fastify/express middleware-compatibility plugin (versions 4.0.6 and earlier) lets unauthent
Authentication bypass in @fastify/express v4.0.4 and earlier allows remote unauthenticated attackers to access protected
Middleware bypass in Fastify Express plugin (fastify/express) allows complete circumvention of authentication, authoriza
Fastify is a web framework with minimal overhead and plugin architecture. Rated high severity (CVSS 8.8), this vulnerabi
Authentication and authorization bypass in @fastify/middie (Node.js middleware library for Fastify) allows remote unauth
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