# Ammonia incorrectly handles embedded SVG and MathML leading to mutation XSS after removal

Source: https://junglewise.ai/threats/ammonia-incorrectly-handles-embedded-svg-and-mathml-leading-to-mutation-c72e022f  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-09-22  
License: CC BY 4.0 with a link back

Severity: medium · CVSS 4 · Published 2025-09-22

Ammonia incorrectly handles embedded SVG and MathML leading to mutation XSS after removal

Technologies: [ammonia (crates.io)](https://junglewise.ai/threats/technologies/ammonia). Vendors: [crates.io](https://junglewise.ai/threats/vendors/crates-io).

## Quick answers

**Is This vulnerability exploited in the wild?** No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

**How severe is This vulnerability?** Medium severity, with a CVSS score of 4, published 22 September 2025.

**Which products and versions are affected?** ammonia (crates.io) SEMVER:introduced=4.1.0,fixed=4.1.2.

**Is there a fix for This vulnerability?** Yes. ammonia (crates.io): upgrade to 4.1.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected?** Check whether you run ammonia (crates.io) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- ammonia (crates.io): upgrade to 4.1.2 or later

  ```sh
  cargo update -p ammonia
  ```


## Affected products

- ammonia (crates.io) SEMVER:introduced=4.1.0,fixed=4.1.2

## Related threats

- [Rust Ammonia XSS via MathML annotation-xml encoding strip](https://junglewise.ai/threats/cve-2026-63430-rustsec-2026-0193-mxss-in-ammonia-via-mathml-annotation-xml)
- [ammonia CSS url function case-sensitivity bypass](https://junglewise.ai/threats/rustsec-2026-0373-missing-case-insensitive-matching-for-css-url-0b78f36f)
- [Ammonia cross-site scripting in SVG animate and set tags](https://junglewise.ai/threats/cve-2026-102342-ammonia-improper-neutralization-of-input-during-web-page)
- [RUSTSEC-2026-0213 - XSS in ammonia via SVG `animate` and `set` animation tags](https://junglewise.ai/threats/rustsec-2026-0213-xss-in-ammonia-via-svg-animate-and-set-animation-tags-3d7360b1)
- [RUSTSEC-2025-0071 - Incorrect handling of embedded SVG and MathML leads to mutation XSS after removal](https://junglewise.ai/threats/rustsec-2025-0071-incorrect-handling-of-embedded-svg-and-mathml-leads-d1eb16ba)