{"id":"CVE-2021-29624","aliases":["GHSA-rc4q-9m69-gqp8"],"url":"https://o3.security/vulnerability/CVE-2021-29624","summary":"Lack of protection against cookie tossing attacks in fastify-csrf","details":"fastify-csrf is an open-source plugin helps developers protect their Fastify server against CSRF attacks. Versions of fastify-csrf prior to 3.1.0 have a \"double submit\" mechanism using cookies with an application deployed across multiple subdomains, e.g. \"heroku\"-style platform as a service. Version 3.1.0 of the fastify-csrf fixes it. the vulnerability. The user of the module would need to supply a `userInfo` when generating the CSRF token to fully implement the protection on their end. This is needed only for applications hosted on different subdomains.","published":"2021-05-19T22:15:07.837Z","modified":"2026-08-27T08:14:28.079376Z","cvss":{"score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"fastify-csrf","fixedVersion":"3.1.0"}],"fix":{"url":"https://github.com/fastify/csrf/pull/2","label":"fastify/csrf#2"},"references":[{"type":"ADVISORY","url":"https://cheatsheetseries.owasp.org/cheatsheets/Cross-Site_Request_Forgery_Prevention_Cheat_Sheet.html"},{"type":"ADVISORY","url":"https://github.com/fastify/fastify-csrf/releases/tag/v3.1.0"},{"type":"ADVISORY","url":"https://owasp.org/www-pdf-archive/David_Johansson-Double_Defeat_of_Double-Submit_Cookie.pdf"},{"type":"FIX","url":"https://github.com/fastify/csrf/pull/2"},{"type":"FIX","url":"https://github.com/fastify/fastify-csrf/pull/51"},{"type":"FIX","url":"https://github.com/fastify/fastify-csrf/security/advisories/GHSA-rc4q-9m69-gqp8"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-27T08:14:28.079376Z"}}