Is CVE-2023-40175 actively exploited?

No active exploitation of CVE-2023-40175 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2023-40175 be exploited remotely?

Yes. CVE-2023-40175 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2023-40175?

CVE-2023-40175 has a CVSS score of 9.8 (CRITICAL).

HOME VULNERABILITIESCVE-2023-40175

CRITICAL

CVE-2023-40175

CWE-444Published: August 18, 2023· Updated: Jun 17, 2026

9.8

CVSS v3.1

Official Description

Puma is a Ruby/Rack web server built for parallelism. Prior to versions 6.3.1 and 5.6.7, puma exhibited incorrect behavior when parsing chunked transfer encoding bodies and zero-length Content-Length headers in a way that allowed HTTP request smuggling. Severity of this issue is highly dependent on the nature of the web site using puma is. This could be caused by either incorrect parsing of trailing fields in chunked transfer encoding bodies or by parsing of blank/zero-length Content-Length headers. Both issues have been addressed and this vulnerability has been fixed in versions 6.3.1 and 5.6.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.

NVD Source

Technical Analysis

CVE-2023-40175 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.