CVE-2021-20220
MEDIUM4.8EPSS 0.18%HTTP request smuggling in Undertow
Published: 6/16/2021Modified: 4/28/2026
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.
Affected packages (2)
- Debian/undertowfrom 0, < 2.2.0-1
- Maven/io.undertow:undertow-core>= 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 |
References (5)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2021-20220
- ADVISORYhttps://security-tracker.debian.org/tracker/CVE-2021-20220
- WEBhttps://bugzilla.redhat.com/show_bug.cgi?id=1923133
- WEBhttps://github.com/undertow-io/undertow/commit/9e797b2f99617fdad0471eaa88c711ee7f44605f
- WEBhttps://security.netapp.com/advisory/ntap-20220210-0013