#VU81803 Exposed dangerous method or function in Apache Tomcat - CVE-2023-42794

Vulnerability identifier: #VU81803

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2023-42794

CWE-ID: CWE-749

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 a denial of service (DoS) attack.

The vulnerability exists due to Tomcat's internal fork of a Commons FileUpload included an unreleased, in progress refactoring that exposed a potential denial of service on Windows. A remote attacker can perform a denial of service attack by uploading multiple files to the server that are not removed.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Apache Tomcat: 8.5.85 - 8.5.93, 9.0.70 - 9.0.80

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External links
https://lists.apache.org/thread/vvbr2ms7lockj1hlhz5q3wmxb2mwcw82
https://github.com/apache/tomcat/commit/c99ffc30e95ddc4daede564d08cb5ea2b9a9da65
https://github.com/apache/tomcat/commit/43b882b8a577684498ab9b8851aa0427216784f7

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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.