Answer in brief
CVE-2023-29019 records a High severity (CVSS 8.1) vulnerability in Session fixation in fastify-passport. The current sources do not mark it as known exploited. The current feed maps @fastify/passport (npm), @fastify/passport (npm). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps @fastify/passport (npm), @fastify/passport (npm). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| @fastify/passportnpm | >=0 <1.1.0 | 1.1.0 |
| @fastify/passportnpm | >=2.0.0 <2.3.0 | 2.3.0 |
Published upstream
Apr 21, 2023
Evidence: source:osv:source_dates:source-dates:recordSource modified
Sep 10, 2026
Evidence: source:osv:source_dates:source-dates:recordFirst seen by HOL
Sep 10, 2026
Applications using `@fastify/passport` for user authentication, in combination with `@fastify/session` as the underlying session management mechanism, are vulnerable to [session fixation attacks](https://owasp.org/www-community/attacks/Session_fixation) from network and same-site attackers. ## Details fastify applications rely on the `@fastify/passport` library for user authentication. The login and user validation are performed by the `authenticate` function. When executing this function, the `sessionId` is preserved between the pre-login and the authenticated session. Network and [same-site attackers](https://canitakeyoursubdomain.name/) can hijack the victim's session by tossing a valid `sessionId` cookie in the victim's browser and waiting for the victim to log in on the website. ## Fix As a solution, newer versions of `@fastify/passport` regenerate `sessionId` upon login, preventing the attacker-controlled pre-session cookie from being upgraded to an authenticated session. ## Credits * Pedro Adão (@pedromigueladao), [Instituto Superior Técnico, University of Lisbon](https://tecnico.ulisboa.pt/) * Marco Squarcina (@lavish), [Security & Privacy Research Unit, TU Wien](https://secpriv.wien/)
Quoted source text, attributed separately from HOL analysis.