CVE-2021-31402: Flutterchina Dio

High severity, CVSS 7.5. EPSS: 1.2% chance of exploitation in the next 30 days.

The dio package 4.0.0 for Dart allows CRLF injection if the attacker controls the HTTP method string, a different vulnerability than CVE-2020-35669.

Affected products

• Flutterchina Dio: from 4.0.0, before 5.0.0 (fixed in 5.0.0)

Published 2021-04-15. Last modified 2026-06-17.