CVE-2018-21035: Qt

High severity, CVSS 7.5. EPSS: 2.3% chance of exploitation in the next 30 days.

In Qt through 5.14.1, the WebSocket implementation accepts up to 2GB for frames and 2GB for messages. Smaller limits cannot be configured. This makes it easier for attackers to cause a denial of service (memory consumption).

Affected products

• Qt Qt: up to and including 5.14.1

Published 2020-02-28. Last modified 2026-06-17.