Puma used with Rails may lead to Information Exposure

Exploitation

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

CVSS

8.0 · CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N

EPSS

• CVE-2022-23634: 2.11% estimated exploitation activity in the next 30 days; percentile 81.78 (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.

Impact Prior to puma version 5.6.2, puma may not always call close on the response body. Rails, prior to version 7.0.2.2, depended on the response body being closed in order for its CurrentAttributes implementation to work correctly. From Rails: Under certain circumstances response bodies will not be closed, for example a bug in a webserver[1] or a bug in a Rack middleware. In the event a response is not notified of a close, ActionDispatch::Executor will not know to reset thread local state for the next request. This can lead to data being leaked to subsequent requests, especially when interacting with ActiveSupport::CurrentAttributes. The combination of these two behaviors (Puma not closing the body + Rails' Executor implementation) causes information leakage. Patches This problem is fixed in Puma versions 5.6.2 and 4.3.11. This problem is fixed in Rails versions 7.02.2, 6.1.4.6, 6.0.4.6, and 5.2.6.2. See: https://github.com/advisories/GHSA-wh98-p28r-vrc9 for details about the rails…

Published by the source

11 Feb 2022, 21:33 UTC

Last modified by the source

13 Jul 2023, 19:09 UTC

Source last checked

26 Oct 2026, 15:47 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-rmj8-8hhh-gv5h

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# Patch Next advisory brief: CVE-2022-23634

Advisory: Puma used with Rails may lead to Information Exposure
IDs: CVE-2022-23634, GHSA-rmj8-8hhh-gv5h
Record: https://patchnext.com/advisories/cve-2022-23634 (revision 1, source checked 26 Oct 2026, 15:47 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.0)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: puma 5.6.2, 4.3.11. A vendor fix does not mean a deployment is fixed.

## Affected components
- RubyGems puma: affected >= 5.0.0, < 5.6.2; < 4.3.11; fixed in 4.3.11, 5.6.2

## Suggested inspection (read-only)
- RubyGems puma: 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 puma.
- 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-rmj8-8hhh-gv5h (GitHub-reviewed advisory GHSA-rmj8-8hhh-gv5h lists affected ranges: RubyGems puma >=5.0.0 =0 <4.3.11)

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