CVE-2026-126078 Action View: Possible XSS vulnerability in Action View highlight helper
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-126078?
CVE-2026-126078 is a medium-severity vulnerability in rails, published on 10 Nov 2026.
Official description
Action View is a framework for handling view template lookup and rendering and provides view helpers for building HTML. Prior to 8.1.4.1 and 8.0.5.2, ActionView::Helpers::TextHelper#highlight substitutes each matched phrase into the :highlighter string without escaping it and returns the result marked HTML-safe. Because sanitizing leaves quote characters in text unescaped, a match substituted into a quoted attribute value of the highlighter, such as the <a href="search?q=\1"> form shown in the method's documentation, could end the attribute value and add attributes to the element, possibly leading to XSS. Applications are affected when they pass a :highlighter that places a placeholder inside an attribute value and highlight text or phrases that a user controls. The default <mark>\1</mark> highlighter and the block form are not affected. This issue is fixed in versions 8.1.4.1 and 8.0.5.2.
Weakness: CWE-79
Which versions are affected by CVE-2026-126078?
2 open source packages ship an affected version, including actionview.
| Package | Affected | Fixed in |
|---|---|---|
actionview RubyGems | All versions | 8.0.5.2 |
actionview RubyGems | From 8.1.0.beta1 | 8.1.4.1 |
How do I fix CVE-2026-126078?
Upgrade actionview to a fixed version for your release line: 8.0.5.2 or 8.1.4.1.
Is CVE-2026-126078 being exploited?
There is no known exploitation of CVE-2026-126078 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-126078, GHSA-v6rj-xm57-3p59, UBUNTU-CVE-2026-126078.