{"api_version":"1","generated_at":"2026-07-24T19:12:21+00:00","cve":"CVE-2021-21321","urls":{"html":"https://cve.report/CVE-2021-21321","api":"https://cve.report/api/cve/CVE-2021-21321.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2021-21321","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-21321"},"summary":{"title":"CVE-2021-21321","description":"fastify-reply-from is an npm package which is a fastify plugin to forward the current http request to another server. In fastify-reply-from before version 4.0.2, by crafting a specific URL, it is possible to escape the prefix of the proxied backend service. If the base url of the proxied server is \"/pub/\", a user expect that accessing \"/priv\" on the target service would not be possible. In affected versions, it is possible. 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In fastify-reply-from before version 4.0.2, by crafting a specific URL, it is possible to escape the prefix of the proxied backend service. If the base url of the proxied server is \"/pub/\", a user expect that accessing \"/priv\" on the target service would not be possible. In affected versions, it is possible. This is fixed in version 4.0.2.","Type":"Description","Title":null},{"CveYear":"2021","CveId":"21321","Ordinal":"2","NoteData":"2021-03-01","Type":"Other","Title":"Published"},{"CveYear":"2021","CveId":"21321","Ordinal":"3","NoteData":"2021-03-01","Type":"Other","Title":"Modified"}]}}}