rails actionview prior 7.2.3.1/8.0.4.1/8.1.2.1 Attribute cross site scripting

Summaryinfo

A vulnerability marked as problematic has been reported in rails actionview. This affects an unknown function of the component Attribute Handler. This manipulation causes cross site scripting. This vulnerability is tracked as CVE-2026-33168. The attack is possible to be carried out remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in rails actionview. Affected by this vulnerability is an unknown code of the component Attribute Handler. The manipulation with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. The summary by CVE is:

Action View provides conventions and helpers for building web pages with the Rails framework. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, when a blank string is used as an HTML attribute name in Action View tag helpers, the attribute escaping is bypassed, producing malformed HTML. A carefully crafted attribute value could then be misinterpreted by the browser as a separate attribute name, possibly leading to XSS. Applications that allow users to specify custom HTML attributes are affected. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-33168 since 03/17/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

Upgrading to version 7.2.3.1, 8.0.4.1 or 8.1.2.1 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 0b6f8002b52b9c606fd6be9e7915d9f944cf539c is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-1687). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• IBM License Metric Tool

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Vendor

• rails

Name

• actionview

License

• open-source

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• 🔒

CPE 2.2info

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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