CVE-2019-18857 is a high-severity (CVSS 7.5) Cross-site Scripting (XSS) vulnerability in enshrined/svg-sanitize. A fix is available for enshrined/svg-sanitize — see the affected versions and patch details below.
XSS in enshrined/svg-sanitize due to mishandled script and data values in attributes
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
enshrined/svg-sanitizeReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
darylldoyle svg-sanitizer before 0.12.0 mishandles script and data values in attributes, as demonstrated by unexpected whitespace such as in the javascript :alert substring.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | enshrined/svg-sanitize | all versions | 0.12.0composer require enshrined/svg-sanitize:^0.12.0 |
Affected Products
svg-sanitizersvg-sanitizer_projectDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for enshrined/svg-sanitize, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update enshrined/svg-sanitize to 0.12.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-18857 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.
Frequently Asked Questions
Is CVE-2019-18857 in your dependencies?
Find it across Packagist, including transitive dependencies.