CVE-2020-28364 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in locust. A fix is available for locust — see the affected versions and patch details below.
Locust Stored Cross-site Scripting Vulnerability
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
locustReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
A stored cross-site scripting (XSS) vulnerability affects the Web UI in Locust before 1.3.2, if the installation violates the usage expectations by exposing this UI to outside users.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | locust | all versions | 1.3.2pip install --upgrade 'locust==1.3.2' |
Affected Products
locustlocustDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for locust, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update locust to 1.3.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-28364 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-2020-28364 in your dependencies?
Find it across PyPI, including transitive dependencies.