HTTP request smuggling in Netty

1) Inconsistent interpretation of HTTP requests

EUVDB-ID: #VU25353

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-7238

CWE-ID: CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling')

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform HTTP request smuggling attack.

The vulnerability exists due to improper input validation when processing a whitespace before the colon in HTTP headers (e.g. "Transfer-Encoding : chunked") and a later Content-Length header. A remote attacker can send a specially crafted HTTP request and perform HTTP request smuggling attack.

This issue exists because of an incomplete fix for CVE-2019-16869 (SB2019092616).

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Netty: 4.1.43 - 4.1.44

External links

http://access.redhat.com/errata/RHSA-2020:0497
http://github.com/jdordonezn/CVE-2020-72381/issues/1
http://netty.io/news/

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.