CVE-2024-29901 in authkit-nextjs
Summary
by MITRE • 03/29/2024
The AuthKit library for Next.js provides helpers for authentication and session management using WorkOS & AuthKit with Next.js. A user can reuse an expired session by controlling the `x-workos-session` header. The vulnerability is patched in v0.4.2.
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Analysis
by VulDB Data Team • 05/08/2025
The CVE-2024-29901 vulnerability affects the AuthKit library for Next.js, which serves as a authentication and session management helper integrating with WorkOS and AuthKit. This library provides developers with tools to implement secure authentication flows within Next.js applications, making it a critical component in modern web application security infrastructure. The vulnerability specifically targets the session validation mechanism within the library's implementation, creating a potential security risk for applications that rely on proper session expiration handling. The flaw manifests when the library fails to properly validate session expiration status, allowing attackers to extend the lifetime of expired sessions through manipulation of HTTP headers.
The technical flaw resides in the improper handling of the x-workos-session header, which serves as a critical authentication token for session management within the WorkOS integration. When an attacker controls this header value, they can effectively bypass session expiration checks that should normally invalidate stale sessions and force users to re-authenticate. This represents a classic session management vulnerability where the system fails to properly validate session state before granting access privileges. The vulnerability allows for session replay attacks where expired session tokens can be reused indefinitely, essentially creating a backdoor for unauthorized access that persists beyond the intended session lifetime. This type of flaw typically stems from insufficient input validation and improper session state management within the authentication middleware layer.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it can enable attackers to maintain persistent access to protected application resources long after legitimate session expiration. Applications using the affected AuthKit library may experience unauthorized data access, privilege escalation, and potential data breaches when attackers leverage this vulnerability to reuse expired sessions. The attack vector is particularly concerning because it requires minimal effort from threat actors who only need to manipulate HTTP headers rather than exploit complex cryptographic weaknesses or bypass strong authentication mechanisms. This vulnerability directly violates security principles outlined in the OWASP Top 10, specifically addressing session management weaknesses that can lead to unauthorized access and data compromise.
Mitigation strategies should focus on immediate patching of the AuthKit library to version 0.4.2, which contains the necessary fixes for the session validation logic. Organizations should also implement comprehensive monitoring of authentication headers and session lifecycle events to detect potential exploitation attempts. Security teams should conduct thorough audits of all applications utilizing the AuthKit library to ensure proper session management implementation and verify that session expiration policies are correctly enforced. Additional defensive measures include implementing rate limiting on authentication endpoints, monitoring for unusual session reuse patterns, and establishing automated alerts for suspicious header manipulation attempts. The vulnerability demonstrates the importance of proper session management practices and highlights the need for regular security assessments of authentication libraries used in production environments. This issue aligns with CWE-613, which addresses insufficient session expiration, and represents a clear violation of the principle of least privilege in access control mechanisms.