RUSTSEC-2026-0213

XSS in ammonia via SVG animate and set animation tags

Reported

July 21, 2026

Issued

July 22, 2026

Package

ammonia (crates.io)

Type

Vulnerability

Categories

format-injection

Keywords

#html #xss

Aliases

GHSA-m6mh-2hw2-555x

Patched

>=4.1.4
>=4.0.3, <4.1.0
>=3.3.3, <4.0.0

Description

The following SVG will produce a link with a javascript scheme. If the user clicks this link, they will run it.

<svg xmlns="http://www.w3.org/2000/svg">
  <a>
    <set attributeName="href" to="javascript:alert('SET_XSS')"></set>
    <text y="30">Click set</text>
  </a>
</svg>

Ammonia did not apply attribute filters based on attributeName, so the contents of the to, from, and values tags were not sanitized as URLs.

Applications that do not explicitly allow either of these tags should not be affected, since neither are allowed by default.

Discovered by: Younghun Ko (@koyokr)

Advisory available under CC0-1.0 license.