CVE-2022-23634
mediumpriority · track · 25EPSS 0.021 · 82 %ileDEEURUUSEPSS · scored 2026-10-27
Puma is a Ruby/Rack web server built for parallelism. 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. The combination of these two behaviors (Puma not closing the body + Rails' Executor implementation) causes information leakage. 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. Upgrading to a patched Rails _or_ Puma version fixes the vulnerability.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixedruby4.0-rubygem-puma-0:6.4.3-1.5.aarch64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedruby4.0-rubygem-puma-0:6.4.3-1.5.ppc64le as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedruby4.0-rubygem-puma-0:6.4.3-1.5.s390x as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedruby4.0-rubygem-puma-0:6.4.3-1.5.x86_64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.3–8
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (30)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- openSUSE-SU-2026:10357-1ruby4.0-rubygem-puma-6.4.3-1.5 on GA media2026-03-13csaf · suse_csafDE
ruby4.0-rubygem-puma-6.4.3-1.5 on GA media
- GHSA-rmj8-8hhh-gv5hPuma used with Rails may lead to Information Exposure2022-02-11ghsa · osvUS
### 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 vulnerability Upgrading to a patched Rails _or_ Puma version fixes the vulnerability. ### Workarounds Upgrade to Rails versions 7.02.2, 6.1.4.6, 6.0.4.6, and 5.2.6.2. The [Rails CVE](https://groups.google.com/g/ruby-security-ann/c/FkTM-_7zSNA/m/K2RiMJBlBAAJ?utm_medium=email&utm_source=footer&pli=1) includes a middleware that can be used instead. ### References * Rails CVE: [CVE-2022-23633](https://groups.google.com/g/ruby-security-ann/c/FkTM-_7zSNA/m/K2RiMJBlBAAJ?utm_medium=email&utm_source=footer&pli=1) ### For more information If you have any questions or comments about this advisory: * Open an issue in [puma](https://github.com/puma/puma) * See our [security policy](https://github.com/puma/puma/security/policy)
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (42)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2022-23634cnnvd
- https://github.com/advisories/GHSA-rmj8-8hhh-gv5hcnnvd
- https://github.com/advisories/GHSA-wh98-p28r-vrc9cnnvd
- https://github.com/puma/puma/commit/b70f451fe8abc0cff192c065d549778452e155bbcnnvd
- https://github.com/puma/puma/security/advisories/GHSA-rmj8-8hhh-gv5hcnnvd
- https://groups.google.com/g/ruby-security-ann/c/FkTM-_7zSNA/m/K2RiMJBlBAAJ?utm_medium=email&utm_source=footer&pli=1cnnvd
- https://lists.debian.org/debian-lts-announce/2022/05/msg00034.htmlcnnvd
- https://lists.debian.org/debian-lts-announce/2022/08/msg00015.htmlcnnvd
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