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TI-2021-10192 Aliases CVE-2021-29479GHSA-w6rq-6h34-vh7q

Cached redirect poisoning via X-Forwarded-Host header

Priority LOW 32CWE-807Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
Low · High · Low
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

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.

Why it matters now

EPSS 0.00857 58th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed ratpack (ratpack): 1.9.0io.ratpack:ratpack-core (Maven): 1.9.0

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
ratpackratpackbefore 1.9.01.9.0Patch availableCNA
—io.ratpack:ratpack-core (Maven)before 1.9.01.9.0Patch availableGHSA-w6rq-6h34-vh7q
  • ratpack Vendorratpack Affected before 1.9.0 Fixed in 1.9.0 Patch available CNA
  • io.ratpack:ratpack-core (Maven) Vendor— Affected before 1.9.0 Fixed in 1.9.0 Patch available GHSA-w6rq-6h34-vh7q

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:ratpack_project:ratpack:*:*:*:*:*:*:*:*before 1.9.0VulnerableRatpack Project
  • cpe:2.3:a:ratpack_project:ratpack:*:*:*:*:*:*:*:* Versions before 1.9.0 Vulnerable ·Ratpack Project

Remediation

  • Fix · CNA ratpack (ratpack) Fixed in 1.9.0
  • Fix · GHSA-w6rq-6h34-vh7q io.ratpack:ratpack-core (Maven) Fixed in 1.9.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-29479
  2. 2026-10-03 Alias added: GHSA-w6rq-6h34-vh7q

References

Exploit 1

Advisory 2

Other 1

  • TI-2021-10198 Remote Code Execution Vulnerability in Session Storage CVSS 3.1CRITICAL 9.9
  • TI-2021-10194 Client side sessions should not allow unencrypted storage CVSS 3.1HIGH 7.5
  • TI-2019-08035 Cross-site scripting in io.ratpack:ratpack-core CVSS 3.1MEDIUM 6.1
  • TI-2021-10193 Default client side session signing key is highly predictable CVSS 3.1MEDIUM 4.4

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences