---
id: "CVE-2026-121447"
kind: "vulnerability"
aliases: ["CVE-2026-121447"]
title: "svg-sanitizer: javascript URLs in animateTransform bypass sanitization, enabling XSS"
severity: "medium"
cvss: 6.1
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["file-upload", "node", "package", "svg-sanitizer", "xss"]
not_affected_if: ["not-using-svg-sanitizer", "sanitized-version-1.1.0", "svg-not-rendered"]
published_at: "2026-11-03T15:17:37+00:00"
first_seen_at: "2026-11-03T15:22:01+00:00"
updated_at: "2026-11-03T15:23:19+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-121447", "first_seen_at": "2026-11-03T15:22:01+00:00"}]
---

# svg-sanitizer: javascript URLs in animateTransform bypass sanitization, enabling XSS

svg-sanitizer before 1.1.0 fails to strip javascript: URLs placed in the animateTransform values attribute, so a crafted SVG can smuggle script through the sanitizer. When a user clicks the resulting link in Safari, arbitrary JavaScript runs in the page's origin.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed version of svg-sanitizer with `npm ls svg-sanitizer` or the lockfile.
- Search your code for places where SVG uploads are sanitized with svg-sanitizer and then rendered inline or served from your domain.

## Fix

- svg-sanitizer `1.1.0` (fixed release per the description: all versions before 1.1.0 are affected).

## Timeline

- 2026-11-03T15:22:01+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-121447

## Documents

- [advisory] Vendor advisory: github.com https://github.com/darylldoyle/svg-sanitizer/security/advisories/GHSA-q546-85r6-f39q
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/svg-sanitizer-before-1.1.0-xss-via-animatetransform-on-safari

## From the sources

svg-sanitizer before 1.1.0 contains a cross-site scripting vulnerability that allows attackers to bypass sanitization by placing javascript: URLs in the animateTransform values attribute. Attackers can upload crafted SVG files whose animateTransform targets the href attribute, executing arbitrary JavaScript when Safari users click the link.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_