Vulnerability identifier: #VU51518

Vulnerability risk: Medium

CVSSv3.1: 6.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-20220

CWE-ID: CWE-444

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Undertow
Server applications / Web servers

Vendor: Red Hat Inc.

Description

The vulnerability allows a remote attacker to preform HTTP request smuggling attacks.

The vulnerability exists due to improper validation of HTTP requests when processing HTTP/1.x and HTTP/2  protocols. A remote attacker can send a specially crafted HTTP request to the server and smuggle arbitrary HTTP headers.

Successful exploitation of vulnerability may allow an attacker to poison HTTP cache and perform phishing attacks.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Undertow: 2.0.0 - 2.1.5

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External links
http://bugzilla.redhat.com/show_bug.cgi?id=1923133

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.