CVE-2026-33167
mediumpriority · track · 24EPSS 0.003 · 18 %ileDEEUUSEPSS · scored 2026-10-27
Action Pack is a Rubygem for building web applications on the Rails framework. In versions on the 8.1 branch prior to 8.1.2.1, the debug exceptions page does not properly escape exception messages. A carefully crafted exception message could inject arbitrary HTML and JavaScript into the page, leading to XSS. This affects applications with detailed exception pages enabled (`config.consider_all_requests_local = true`), which is the default in development. Version 8.1.2.1 contains a 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 · low–medium · 1.3–6.1
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
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affected products (9)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-0833Ruby on Rails: Mehrere SchwachstellenDeutsch2026-03-23csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Ruby on Rails ausnutzen, um einen Denial of Service Angriff durchzuführen, um Dateien zu manipulieren, und um einen Cross-Site Scripting Angriff durchzuführen.
- GHSA-pgm4-439c-5jp6Rails has a possible XSS vulnerability in its Action Pack debug exceptions2026-03-23ghsa · osvUS
### Impact The debug exceptions page does not properly escape exception messages. A carefully crafted exception message could inject arbitrary HTML and JavaScript into the page, leading to XSS. This affects applications with detailed exception pages enabled (`config.consider_all_requests_local = true`), which is the default in development. ### Releases The fixed releases are available at the normal locations. ### Credit This issue was responsibly reported by Hackerone researcher [fbettag](https://hackerone.com/fbettag).
also known as (3)
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sources
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references (11)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2026-33167cnnvd
- https://github.com/rails/rails/commit/6752711c8c31d79ba50d13af6a6698a3b85415e0cnnvd
- https://github.com/rails/rails/releasesPatchcnnvd
- https://github.com/rails/rails/releases/tag/v8.1.2.1cnnvd
- https://github.com/rails/rails/security/advisories/GHSA-pgm4-439c-5jp6cnnvd
- https://github.com/rails/rails/commit/6752711c8c31d79ba50d13af6a6698a3b85415e0enisa_euvd
- https://github.com/rails/rails/releases/tag/v8.1.2.1enisa_euvd
- https://github.com/rails/rails/security/advisories/GHSA-pgm4-439c-5jp6enisa_euvd
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