CVE-2021-21409: Debian Linux

Medium severity, CVSS 5.9. EPSS: 4.9% chance of exploitation in the next 30 days.

Netty is an open-source, asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In Netty (io.netty:netty-codec-http2) before version 4.1.61.Final there is a vulnerability that enables request smuggling. The content-length header is not correctly validated if the request only uses a single Http2HeaderFrame with the endStream set to to true. This could lead to request smuggling if the request is proxied to a remote peer and translated to HTTP/1.1. This is a followup of GHSA-wm47-8v5p-wjpj/CVE-2021-21295 which did miss to fix this one case. This was fixed as part of 4.1.61.Final.

Affected products

  • Debian Debian Linux: version 10.0 only
  • Netapp Oncommand API Services: affected versions not specified
  • Netapp Oncommand Workflow Automation: affected versions not specified
  • Netty Netty: before 4.1.61 (fixed in 4.1.61)
  • Oracle Banking Corporate Lending Process Management: version 14.2.0 only; version 14.3.0 only; version 14.5.0 only
  • Oracle Banking Credit Facilities Process Management: version 14.2.0 only; version 14.3.0 only; version 14.5.0 only
  • Oracle Banking Trade Finance Process Management: version 14.2.0 only; version 14.3.0 only; version 14.5.0 only
  • Oracle Coherence: version 12.2.1.4.0 only; version 14.1.1.0.0 only
  • Oracle Communications Brm - Elastic Charging Engine: version 12.0.0.3 only
  • Oracle Communications Cloud Native Core Console: version 1.7.0 only
  • Oracle Communications Cloud Native Core Policy: version 1.14.0 only
  • Oracle Communications Design Studio: version 7.4.2.0.0 only
  • Oracle Communications Messaging Server: version 8.1 only
  • Oracle Helidon: version 1.4.10 only; version 2.4.0 only
  • Oracle Jd Edwards Enterpriseone Tools: before 9.2.6.3 (fixed in 9.2.6.3)
  • Oracle Nosql Database: before 21.1.12 (fixed in 21.1.12)
  • Oracle Primavera Gateway: from 17.12.0, up to and including 17.12.11; from 18.8.0, up to and including 18.8.11; from 19.12.0, up to and including 19.12.10
  • Quarkus Quarkus: up to and including 1.13.7

Published 2021-03-30. Last modified 2026-10-08.