{"cve":"CVE-2021-29479","nvd":{"published":"2021-06-29T15:15:18.870","modified":"2026-06-17T03:47:43.630","status":"Modified","description":"Ratpack is a toolkit for creating web applications. In versions prior to 1.9.0, a user supplied `X-Forwarded-Host` header can be used to perform cache poisoning of a cache fronting a Ratpack server if the cache key does not include the `X-Forwarded-Host` header as a cache key. Users are only vulnerable if they do not configure a custom `PublicAddress` instance. For versions prior to 1.9.0, by default, Ratpack utilizes an inferring version of `PublicAddress` which is vulnerable. This can be used to perform redirect cache poisoning where an attacker can force a cached redirect to redirect to their site instead of the intended redirect location. The vulnerability was patched in Ratpack 1.9.0. As a workaround, ensure that `ServerConfigBuilder::publicAddress` correctly configures the server in production.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","score":6.1},"cwes":["CWE-807"],"references":["https://github.com/ratpack/ratpack/security/advisories/GHSA-w6rq-6h34-vh7q","https://portswigger.net/web-security/web-cache-poisoning","https://github.com/ratpack/ratpack/security/advisories/GHSA-w6rq-6h34-vh7q","https://portswigger.net/web-security/web-cache-poisoning"],"products":["ratpack_project:ratpack"],"source":"nvd","synced_at":"2026-10-19T21:20:07.141963181+00:00"},"epss":{"cve":"CVE-2021-29479","score":0.00857,"percentile":0.58433,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-w6rq-6h34-vh7q","url":"https://osv.dev/vulnerability/GHSA-w6rq-6h34-vh7q","summary":"Cached redirect poisoning via X-Forwarded-Host header","modified":"2026-07-08T06:29:24.395736755Z","packages":[{"ecosystem":"Maven","name":"io.ratpack:ratpack-core","purl":"pkg:maven/io.ratpack/ratpack-core","ranges":["<1.9.0"],"fixed":["1.9.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}