Default development error handler in Ratpack is vulnerable to HTML content injection (XSS)

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.1 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS

• CVE-2019-10770: 0.86% estimated exploitation activity in the next 30 days; percentile 58.49 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Versions of Ratpack from 0.9.10 through 1.7.5 are vulnerable to CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (aka. XSS) in the development error handler. An attacker can utilize this to perform XSS when an exception message contains untrusted data. As a simplistic example: Impact - Cross-Site Scripting Patches This vulnerability has been patched in Ratpack version 1.7.6. Workarounds If you are unable to update your version of Ratpack, we recommend the following workarounds and mitigations. - Ensure that development mode is disabled in production. - Don't use real customer data (ie. untrusted user input) in development. References - Ratpack development mode - Code Patch - a3cbb13 For more information If you have any questions or comments about this advisory: - Open an issue in ratpack/ratpack - Ask in our Slack channel

Published by the source

27 Jan 2020, 19:28 UTC

Last modified by the source

7 Sep 2023, 20:42 UTC

Source last checked

26 Oct 2026, 16:12 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-r2wf-q3x4-hrv9

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# Patch Next advisory brief: CVE-2019-10770

Advisory: Default development error handler in Ratpack is vulnerable to HTML content injection (XSS)
IDs: CVE-2019-10770, GHSA-r2wf-q3x4-hrv9
Record: https://patchnext.com/advisories/cve-2019-10770 (revision 1, source checked 26 Oct 2026, 16:12 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: io.ratpack:ratpack-core 1.7.6. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven io.ratpack:ratpack-core: affected < 1.7.6; fixed in 1.7.6

## Suggested inspection (read-only)
- Maven io.ratpack:ratpack-core: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on io.ratpack:ratpack-core.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-r2wf-q3x4-hrv9 (GitHub-reviewed advisory GHSA-r2wf-q3x4-hrv9 lists affected ranges: Maven io.ratpack:ratpack-core >=0 <1.7.6)

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