CVE-2020-36319 is a medium-severity (CVSS 6.5) Information Exposure vulnerability in com.vaadin:flow-server. O3 Security confirms whether CVE-2020-36319 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Potential sensitive data exposure in applications using Vaadin 15
Real-World Exposure
com.vaadin:flow-serverReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Insecure configuration of default ObjectMapper in com.vaadin:flow-server versions 3.0.0 through 3.0.5 (Vaadin 15.0.0 through 15.0.4) may expose sensitive data if the application also uses e.g. @RestController
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | com.vaadin:flow-server | ≥ 3.0.0&&< 3.0.6 | 3.0.6 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for com.vaadin:flow-server. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update com.vaadin:flow-server to 3.0.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-36319 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2020-36319 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2020-36319. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2020-36319 in your dependencies?
O3 detects CVE-2020-36319 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.