CVE-2021-20220
HTTP request smuggling in Undertow
4.8
MEDIUM
CVSS 3.1
EPSS 0.18%
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.
How to fix CVE-2021-20220
To remediate CVE-2021-20220, upgrade the affected package to a fixed version below.
- —upgrade to 2.2.0-1 or later
- —upgrade to 2.1.6 or later
Is CVE-2021-20220 being exploited?
Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 2.2.0-1
- >= 2.1.0, < 2.1.6
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM4.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N |