What is CVE-2019-25027?

CVE-2019-25027 is a medium-severity vulnerability in Vaadin Flow, classified under CWE-81. CVSS score: 6.1/10. Published 2021-04-23.

How severe is CVE-2019-25027?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Vaadin Flow

CVE-2019-25027

Missing output sanitization in default RouteNotFoundError view in com.vaadin:flow-server versions 1.0.0 through 1.0.10 (Vaadin 10.0.0 through 10.0.13), and 1.1.0 through 1.4.2 (Vaadin 11.0.0 through 13.0.5) allows attacker to execute malicious JavaScript via crafted URL

Published 2021-04-23 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.007 (50.9th percentile), scored 2026-10-19.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 51st percentile — 50.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000

Affected products

Vaadin Flow
Vaadin Flow-Server — versions 1.0.0
Vaadin — versions 10.0.0

Weakness classification (CWE)

References

vaadin.com/security/cve-2019-25027 (Vendor Advisory)
github.com/vaadin/flow/pull/5498 (Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2019-25027?: CVE-2019-25027 is a medium-severity vulnerability in Vaadin Flow, classified under CWE-81. CVSS score: 6.1/10. Published 2021-04-23.
How severe is CVE-2019-25027?: Medium severity. CVSS v3 base score is 6.1 out of 10.