CVE-2026-33167

Rails has a possible XSS vulnerability in its Action Pack debug exceptions

Published: Mar 23, 2026Updated: Aug 12, 2026 Sources: CVE List NVDCWE-79

6.1MEDIUM

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:RUser Interaction

Required

Scope

S:CScope

Changed

Impact

C:LConfidentiality

Low

I:LIntegrity

Low

A:NAvailability

None

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Weaknesses

CWE-79

Affected Products

rubyonrails

oss-project·USaka rubyonrails.org, ruby on rails, rails

rails

OSS Libraries

rails

oss-projectaka rails-html-sanitizer, activestorage

actionpackLibrary

OSS Libraries / web-framework

Exploitability

Official Patch Available

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Execution

Initial Access

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References

https://github.com/rails/rails/commit/6752711c8c31d79ba50d13af6a6698a3b85415e0

github.com

https://github.com/rails/rails/releases/tag/v8.1.2.1

github.com

https://github.com/rails/rails/security/advisories/GHSA-pgm4-439c-5jp6

github.com

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