#VU68859 Inconsistent interpretation of HTTP requests in Apache Tomcat - CVE-2022-42252

Vulnerability identifier: #VU68859

Vulnerability risk: Medium

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2022-42252

CWE-ID: CWE-444

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Apache Tomcat
Server applications / Web servers

Vendor: Apache Foundation

Description

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

The vulnerability exists due to improper validation of HTTP requests. A remote attacker can send a specially crafted HTTP request to the server and smuggle arbitrary HTTP headers via an invalid Content-Length header.

Successful exploitation of vulnerability may allow an attacker to poison HTTP cache and perform phishing attacks but requires Tomcat to be configured to ignore invalid HTTP headers via setting rejectIllegalHeader to false (not the default configuration).

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Apache Tomcat: 8.5.0 - 8.5.82, 9.0.0-M1 - 9.0.67, 10.0.0-M1 - 10.0.26, 10.1.0-M1 - 10.1.0

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External links
https://tomcat.apache.org/security-10.html
https://tomcat.apache.org/security-9.html
https://tomcat.apache.org/security-8.html

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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.