Summary
Ammonia incorrectly handles embedded SVG and MathML leading to mutation XSS after removal
Affected versions of this crate did not correctly strip namespace-incompatible tags
in certain situations, causing it to incorrectly account for differences between HTML,
SVG, and MathML.
This vulnerability only has an effect when the svg or math tag is allowed,
because it relies on a tag being parsed as html during the cleaning process, but
serialized in a way that causes in to be parsed as xml by the browser.
Additionally, the application using this library must allow a tag that is parsed as raw text in HTML.
These elements are:
- title
- textarea
- xmp
- iframe
- noembed
- noframes
- plaintext
- noscript
- style
- script
Applications that do not explicitly allow any of these tags should not be affected, since none are allowed by default.
Impact
Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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ammonia to 4.1.2 or later; ammonia to 4.0.1 or later; ammonia to 3.3.1 or later
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is GHSA-MM7X-QFJJ-5G2C? GHSA-MM7X-QFJJ-5G2C is a low-severity cross-site scripting (XSS) vulnerability in ammonia (rust), affecting versions >= 4.1.0, < 4.1.2. It is fixed in 4.1.2, 4.0.1, 3.3.1. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
- Which versions of ammonia are affected by GHSA-MM7X-QFJJ-5G2C? ammonia (rust) versions >= 4.1.0, < 4.1.2 is affected.
- Is there a fix for GHSA-MM7X-QFJJ-5G2C? Yes. GHSA-MM7X-QFJJ-5G2C is fixed in 4.1.2, 4.0.1, 3.3.1. Upgrade to this version or later.
- Is GHSA-MM7X-QFJJ-5G2C exploitable, and should I be worried? Whether GHSA-MM7X-QFJJ-5G2C is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether GHSA-MM7X-QFJJ-5G2C is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix GHSA-MM7X-QFJJ-5G2C?
- Upgrade
ammoniato 4.1.2 or later - Upgrade
ammoniato 4.0.1 or later - Upgrade
ammoniato 3.3.1 or later
- Upgrade