CVE-2026-33168 Rails has a possible XSS vulnerability in its Action View tag helpers
Attackers can execute arbitrary scripts via XSS in Rails Action View tag helpers when users control HTML attribute names.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-33168?
CVE-2026-33168 is a low-severity cross-site scripting vulnerability in rails actionview, published on 23 Mar 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-79
Which versions are affected by CVE-2026-33168?
6 open source packages ship an affected version, including actionview.
| Package | Affected | Fixed in |
|---|---|---|
actionview RubyGems | All versions | 7.2.3.1 |
actionview RubyGems | All versions | 7.2.3.1 |
actionview RubyGems | From 8.0.0.beta1 | 8.0.4.1 |
actionview RubyGems | From 8.0.0.beta1 | 8.0.4.1 |
actionview RubyGems | From 8.1.0.beta1 | 8.1.2.1 |
actionview RubyGems | From 8.1.0.beta1 | 8.1.2.1 |
How do I fix CVE-2026-33168?
Upgrade actionview to a fixed version for your release line: 7.2.3.1, 8.0.4.1 or 8.1.2.1.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-33168 being exploited?
There is no known exploitation of CVE-2026-33168 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-33168, GHSA-v55j-83pf-r9cq, UBUNTU-CVE-2026-33168.