CVE-2020-5207: JetBrains Ktor

High severity, CVSS 7.5. EPSS: 0.8% chance of exploitation in the next 30 days.

In Ktor before 1.3.0, request smuggling is possible when running behind a proxy that doesn't handle Content-Length and Transfer-Encoding properly or doesn't handle \n as a headers separator.

Affected products

• JetBrains Ktor: before 1.3.0 (fixed in 1.3.0)

Published 2020-01-27. Last modified 2026-06-17.