XSS in Drupal Term Reference Tree

CVE-2026-4093

In the Drupal 7 Term Reference Tree module, two stored XSS vectors exist in the widget/formatter rendering pipeline. Vector A (token display templates): When the Token module is enabled and token display templates are configured, attacker-controlled token output (e.g., term description) is rendered without proper sanitization. Any user who can edit the referenced taxonomy terms can inject HTML/JS that executes when the field is rendered. Vector B (term label rendering): Taxonomy term labels are not properly sanitized before being rendered in the widget, allowing a user with permission to create or edit taxonomy terms to inject scripts into the term name that execute when a form containing the widget is viewed. Exploit affects versions 7.x-1.x up to and including 7.x-1.11.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (15.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 15th percentile — 15.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-4093: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-4093?
CVE-2026-4093 is a medium-severity vulnerability in Drupal Term Reference Tree, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-05-21.
How severe is CVE-2026-4093?
Medium severity. CVSS v3 base score is 5.4 out of 10.