CVE-2021-21409
5.9 · MEDIUMOverview
CVE-2021-21409 is a medium-severity vulnerability affecting netty netty. It was published on March 30, 2021 and has a CVSS 3.1 base score of 5.9 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.9, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
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.
Remediation
Check the references section for vendor advisories and patches from netty. Update netty to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| netty | netty | >= 0, < 4.1.61 | Affected |
| oracle | jd_edwards_enterpriseone_tools | >= 0, < 9.2.6.3 | Affected |
| oracle | nosql_database | >= 0, < 21.1.12 | Affected |
| oracle | primavera_gateway | 17.12.0 | Affected |
| quarkus | quarkus | 0 | Affected |
References
Frequently Asked Questions
What is CVE-2021-21409?
CVE-2021-21409 is a medium-severity vulnerability affecting netty netty. It was published on March 30, 2021 and has a CVSS 3.1 base score of 5.9 (MEDIUM).
How severe is CVE-2021-21409?
This vulnerability has a CVSS 3.1 base score of 5.9, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2021-21409?
Check the references section for vendor advisories and patches from netty. Update netty to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-21409?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-21409 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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