CVE-2026-33167

Published Mar 23, 2026

Last updated a month ago

CVSS low 1.3
Rails

Overview

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.
Source
security-advisories@github.com
NVD status
Awaiting Analysis

Risk scores

CVSS 4.0

Type
Secondary
Base score
1.3
Impact score
-
Exploitability score
-
Vector string
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Severity
LOW

Weaknesses

security-advisories@github.com
CWE-79

Social media

Hype score
Not currently trending

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References

Sources include official advisories and independent security research.