CVE-2023-40044
WS_FTP Server Ad Hoc Transfer Module .NET Deserialization Vulnerability
- Published
- Updated
- Reserved
- Assigned by
- ProgressSoftware
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.
Exploited in the wild
CISA lists this vulnerability in its Known Exploited Vulnerabilities catalog as Progress WS_FTP Server Deserialization of Untrusted Data Vulnerability.
- Added
- 5 Oct 2023
- Fix due (US federal)
- 26 Oct 2023
- Used by ransomware
- Known
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: it is being exploited.
Timeline
ID reserved
By ProgressSoftware
- 50 days later
· 50 days later
Published
- 8 days later
· 8 days later
Added to CISA KEV
Known exploited, also by ransomware
- 2 years later
· 2 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| ProgressSoftwareCNA (assigner) | 3.1 | Critical10.0 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
| NVDNVD · Analyzed | 3.1 | High8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 90.4% · top 0.2% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: active · Automatable: yes · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 10.0.
Weakness
Affected products
Progress Software Corporation · WS_FTP Server
- affected 8.8.0 – < 8.8.2
- affected 8.7.0 – < 8.7.4
References (9)
- https://www.progress.com/ws_ftp (opens in a new tab)productx_transferred
- https://community.progress.com/s/article/WS-FTP-Server-Critical-Vulnerability-September-2023 (opens in a new tab)vendor-advisoryx_transferred
- https://www.theregister.com/2023/10/02/ws_ftp_update/ (opens in a new tab)x_transferred
- https://www.rapid7.com/blog/post/2023/09/29/etr-critical-vulnerabilities-in-ws_ftp-server/ (opens in a new tab)x_transferred
- https://attackerkb.com/topics/bn32f9sNax/cve-2023-40044 (opens in a new tab)x_transferred
- https://censys.com/cve-2023-40044/ (opens in a new tab)x_transferred
- https://www.assetnote.io/resources/research/rce-in-progress-ws-ftp-ad-hoc-via-iis-http-modules-cve-2023-40044 (opens in a new tab)x_transferred
- http://packetstormsecurity.com/files/174917/Progress-Software-WS_FTP-Unauthenticated-Remote-Code-Execution.html (opens in a new tab)x_transferred
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-40044 (opens in a new tab)government-resource
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- CISA KEV catalog (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2023-40044)Record last updated .