CVE-2021-20220 - CVE House
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Status published Medium CVE-2021-20220

A flaw was found in Undertow. A regression in the...

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

undertow
Vulnerable Versions:
Undertow 2.2.0.Final, Undertow 2.1.6.Final, Undertow 2.0.34.Final

Timeline

Official Publish: February 23rd, 2021
Last Modified: August 3rd, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

Weaknesses (CWE)

CWE-444

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1565.002 Stored Data Manipulation
Impact
T1078 Valid Accounts
Defense Evasion