Trix: Stored XSS vulnerability through serialized attributes

published 2026-03-12 7 mo ago modified 2026-10-22 17 d ago also GHSA-qmpg-8xg6-ph5q , EUVD-2026-60825

cvss: 4.6; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 25%
public exploits: 0; none known

Trix is a what-you-see-is-what-you-get rich text editor for everyday writing. Prior to 2.1.17, Trix is vulnerable to cross-site scripting when a data-trix-serialized-attributes attribute bypasses the DOMPurify sanitizer. An attacker can craft HTML containing a data-trix-serialized-attributes attribute with a malicious payload that, when rendered, executes arbitrary JavaScript in the user's session and may perform unauthorized actions or disclose sensitive information. This issue is fixed in version 2.1.17.

Patch / fix

fixed in 2 links 4

rubygems action_text-trix 2.1.17
npm trix 2.1.17

github.com/basecamp/trix@3229c29 commit
github.com/basecamp/trix@53197ab commit
github.com/basecamp/trix#1282 pull request
github.com/basecamp/trix/releases/tag/v2.1.17 release

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-73426 updated 2026-09-24 cvss 4.6

action_text-trix: trix: Trix: Cross-site scripting via serialized attributes bypass

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2 mo ago (2026-08-18)

Exploit prediction

0.32% chance of exploitation in the next 30 days, higher than 25% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	4.6	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
GitHub	3.1	4.6	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N

Affected packages

ecosystem	package	affected	fixed in
rubygems	action_text-trix	<2.1.17	2.1.17
npm	trix	<2.1.17	2.1.17

Affected products

basecamp trix

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary