CVE-2021-20220
4.8 · MEDIUMOverview
CVE-2021-20220 is a medium-severity vulnerability affecting redhat undertow. It was published on February 23, 2021 and has a CVSS 3.1 base score of 4.8 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 4.8, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
A flaw was found in Undertow. A regression in the fix for CVE-2020-10687 was found. HTTP request smuggling related to CVE-2017-2666 is possible against HTTP/1.x and HTTP/2 due to permitting invalid characters in an HTTP request. This flaw allows an attacker to poison a web-cache, perform an XSS attack, or obtain sensitive information from request other than their own. The highest threat from this vulnerability is to data confidentiality and integrity.
Remediation
Check the references section for vendor advisories and patches from redhat. Update undertow 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 |
|---|---|---|---|
| redhat | undertow | >= 0, < 2.0.34 | Affected |
Frequently Asked Questions
What is CVE-2021-20220?
CVE-2021-20220 is a medium-severity vulnerability affecting redhat undertow. It was published on February 23, 2021 and has a CVSS 3.1 base score of 4.8 (MEDIUM).
How severe is CVE-2021-20220?
This vulnerability has a CVSS 3.1 base score of 4.8, 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-2021-20220?
Check the references section for vendor advisories and patches from redhat. Update undertow 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-2021-20220?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-20220 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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