# CVE-2023-40044: Progress WS_FTP Server Deserialization of Untrusted Data

> A pre-authenticated attacker can execute remote commands on WS_FTP Server via a .NET deserialization flaw in the Ad Hoc Transfer module.

- **Severity:** Critical 10.0 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Yes, since 5 Oct 2023 (CISA KEV), used in ransomware
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 27 Sep 2023
- **Updated:** 21 Oct 2025
- **Also known as:** GHSA-29vf-j74g-gmfc

## What is CVE-2023-40044?

CVE-2023-40044 is a critical unsafe deserialization vulnerability in Progress Software Corporation WS_FTP Server, published on 27 Sep 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official 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.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2023-40044?

It affects 1 product.


Products: Progress Ws Ftp Server.

## How do I fix CVE-2023-40044?

No fix has been published for CVE-2023-40044 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 26 Oct 2023.

## Is CVE-2023-40044 being exploited?

Yes. Attackers have exploited CVE-2023-40044 in the wild since at least 5 Oct 2023, including in ransomware campaigns.

Public exploit code:

- Analysis of WS_FTP CVE (github_poc): https://github.com/kenbuckler/WS_FTP-CVE-2023-40044
- Progress Software WS_FTP Unauthenticated Remote Code Execution (metasploit)
- WS_FTP Server - Insecure Deserialization (nuclei): http/cves/2023/CVE-2023-40044.yaml

## Other vulnerabilities in Progress Software Corporation WS_FTP Server

- [CVE-2023-42657](https://insights.sbomify.com/CVE-2023-42657/): WS_FTP Server Directory Traversal (critical 9.9)
- [CVE-2023-42659](https://insights.sbomify.com/CVE-2023-42659/): WS_FTP Server Arbitrary File Upload (critical 9.1)
- [CVE-2008-0590](https://insights.sbomify.com/CVE-2008-0590/): Memory corruption in n/a (critical 9.0)
- [CVE-2023-40045](https://insights.sbomify.com/CVE-2023-40045/): WS_FTP Server Ad Hoc Transfer Module Reflected Cross-Site Scripting Vulnerability (high 8.3)
- [CVE-2023-40047](https://insights.sbomify.com/CVE-2023-40047/): WS_FTP Server Stored Cross-Site Scripting Vulnerability (high 8.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-40044 and fix it if it is affected.

What it is: CVE-2023-40044 is a critical unsafe deserialization vulnerability in Progress Software Corporation WS_FTP Server, published on 27 Sep 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2023-40044 in the wild since at least 5 Oct 2023, including in ransomware campaigns.

Affected product: Progress Software Corporation WS_FTP Server. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2023-40044/ (Markdown: https://insights.sbomify.com/CVE-2023-40044/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-40044
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-40044
- OSV: https://osv.dev/vulnerability/CVE-2023-40044

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From sbomify Insights: https://insights.sbomify.com/CVE-2023-40044/
Summaries are generated and may contain mistakes; the official description above is the record.