CVE-2023-40044

Name: CVE-2023-40044
Creator: NVD / NIST
Published: 2023-09-27T15:18:57.307+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10Actively ExploitedEPSS 90.15%

Last modified Jun 17, 2026

CVE-2023-40044 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. In WS_FTP Server versions prior to 8.7.4 and 8.8.2, a pre-authenticated attacker could leverage a .NET deserialization vulnerability in the Ad Hoc Transfer module to execute remote commands on the underlying WS_FTP Server operating system.. CISA has confirmed active exploitation in the wild. EPSS estimates a 90.15% chance of exploitation in the next 30 days.

Description

In WS_FTP Server versions prior to 8.7.4 and 8.8.2, a pre-authenticated attacker could leverage a .NET deserialization vulnerability in the Ad Hoc Transfer module to execute remote commands on the underlying WS_FTP Server operating system.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

90.15%

99.8th percentile

Probability of exploitation in the next 30 days. Learn more

Exploitation Status

This vulnerability is listed in CISA’s Known Exploited Vulnerabilities catalog, confirming active exploitation in the wild. Federal agencies must remediate by Oct 26, 2023.

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Progress	Ws Ftp Server	< 8.7.4
Progress	Ws Ftp Server	>= 8.8, < 8.8.2

References

http://packetstormsecurity.com/files/174917/Progress-Software-WS_FTP-Unauthenticated-Remote-Code-Execution.htmlExploit, Third Party Advisory, VDB Entry
https://attackerkb.com/topics/bn32f9sNax/cve-2023-40044Third Party Advisory
https://censys.com/cve-2023-40044/Third Party Advisory
https://community.progress.com/s/article/WS-FTP-Server-Critical-Vulnerability-September-2023Vendor Advisory
https://www.assetnote.io/resources/research/rce-in-progress-ws-ftp-ad-hoc-via-iis-http-modules-cve-2023-40044Exploit, Third Party Advisory
https://www.progress.com/ws_ftpProduct
https://www.rapid7.com/blog/post/2023/09/29/etr-critical-vulnerabilities-in-ws_ftp-server/Broken Link, Third Party Advisory
https://www.theregister.com/2023/10/02/ws_ftp_update/Press/Media Coverage, Third Party Advisory
http://packetstormsecurity.com/files/174917/Progress-Software-WS_FTP-Unauthenticated-Remote-Code-Execution.htmlExploit, Third Party Advisory, VDB Entry
https://attackerkb.com/topics/bn32f9sNax/cve-2023-40044Third Party Advisory
https://censys.com/cve-2023-40044/Third Party Advisory
https://community.progress.com/s/article/WS-FTP-Server-Critical-Vulnerability-September-2023Vendor Advisory
https://www.assetnote.io/resources/research/rce-in-progress-ws-ftp-ad-hoc-via-iis-http-modules-cve-2023-40044Exploit, Third Party Advisory
https://www.progress.com/ws_ftpProduct
https://www.rapid7.com/blog/post/2023/09/29/etr-critical-vulnerabilities-in-ws_ftp-server/Broken Link, Third Party Advisory
https://www.theregister.com/2023/10/02/ws_ftp_update/Press/Media Coverage, Third Party Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-40044US Government Resource

Timeline

Published: Sep 27, 2023
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2023-40044?

How severe is CVE-2023-40044?

CVE-2023-40044 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 90.15% probability of exploitation in the next 30 days. This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog.

How do I fix CVE-2023-40044?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2023-40044?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST