#VU25353 Inconsistent interpretation of HTTP requests in Netty - CVE-2020-7238

Vulnerability identifier: #VU25353

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-7238

CWE-ID: CWE-444

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Netty
Universal components / Libraries / Libraries used by multiple products

Vendor: Netty project

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

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

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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.