When the Vaadin Upload's start listener is used to validate metadata about an incoming upload, it is possible to bypass the upload validation. Users of affected versions should apply the following mitigation or upgrade. Releases that have fixed this issue include: Product version Vaadin 7.0.0 - 7.7.47 Vaadin 8.0.0 - 8.28.1 Vaadin 14.0.0 - 14.13.0 Vaadin 23.0.0 - 23.6.1 Vaadin 24.0.0 - 24.7.6 Mitigation Upgrade to 7.7.48 Upgrade to 8.28.2 Upgrade to 14.13.1 Upgrade to 23.6.2 Upgrade to 24.7.7 or newer Please note that Vaadin versions 10-13 and 15-22 are no longer supported and you should update either to the latest 14, 23, 24 version. Artifacts     Maven coordinatesVulnerable versionsFixed versioncom.vaadin:vaadin-server 7.0.0 - 7.7.47 ≥7.7.48 com.vaadin:vaadin-server 8.0.0 - 8.28.1 ≥8.28.2 com.vaadin:vaadin 14.0.0 - 14.13.0 ≥14.13.1 com.vaadin:vaadin23.0.0 - 23.6.1 ≥23.6.2 com.vaadin:vaadin24.0.0 - 24.7.6 ≥24.7.7com.vaadin:vaadin-upload-flow 2.0.0 - 14.13.0 ≥14.13

Vaadin Framework possible file bypass via upload validation on the server-side