CVE-2021-23339: Lightbend Akka-HTTP

Medium severity, CVSS 6.5. EPSS: 0.7% chance of exploitation in the next 30 days.

This affects all versions before 10.1.14 and from 10.2.0 to 10.2.4 of package com.typesafe.akka:akka-http-core. It allows multiple Transfer-Encoding headers.

Affected products

• Lightbend Akka-HTTP: before 10.1.14 (fixed in 10.1.14); from 10.2.0, before 10.2.4 (fixed in 10.2.4)

Published 2021-02-17. Last modified 2026-06-17.