NVD / CVE Program· CNA ProgressSoftware

CVE-2023-40044: WS_FTP Server Ad Hoc Transfer Module .NET Deserialization Vulnerability

Noroxi assessment

Priority: Now (action score 92/100)

CISA has confirmed exploitation in the wild (Oct 5, 2023); it is known to be used in ransomware campaigns. Remediation deadline for US federal agencies: Oct 26, 2023.
A ready-made attack module is public (Metasploit, Nuclei); exploiting it takes no special expertise.
Probability of exploitation in the next 30 days: 90.3% (FIRST EPSS); higher than 99.7% of all records.
Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
According to CISA the attack is automatable: targets can be found by mass scanning.
Fixed version: Progress Software Corporation WS_FTP Server 8.7.4, 8.8.2.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Patch today or shut off access. Upgrade to Progress Software Corporation WS_FTP Server 8.7.4, 8.8.2 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · CISA KEV · FIRST EPSS

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.

HighCVSS 8.8 · v3.1KEVWeaponized Fix available

Deserialization

BDU:2023-06356

Published: Sep 27, 2023
Updated: Jun 17, 2026
EPSS: 90.3% · 99th percentile
CWE: CWE-502

Report tools

JSON

Action score

Now

Patch today or shut off access.

CVSS: 35 / 40 · 8.8 / 10
CISA KEV: 30 / 30 · Listed
EPSS: 27 / 30 · 90.3%

CISA SSVC decision

Exploitation: active
Automatable: yes
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: 8.8
CNA · ProgressSoftware: 10.0; 1.2 point gap

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

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Actively exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on Oct 5, 2023. That signals real attacks, not theory.

Remediation deadline for US federal agencies: Oct 26, 2023.

Known to be used in ransomware campaigns.

Get told when this record changes

In CISA KEV: exploitation in the wild confirmed
Weaponized exploit exists
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
progress	ws ftp server	cpe:2.3:a:progress:ws_ftp_server

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

progress ws ftp serverbefore 8.7.4
progress ws ftp server8.8 and later · before 8.8.2

Versions reported by the vendor

Affected version ranges reported by the assigning authority (ProgressSoftware). Independent of NVD's CPE analysis and usually ahead of it.

Progress Software Corporation WS_FTP Server
- 8.8.0 and later · before 8.8.2affected · semver
- 8.7.0 and later · before 8.7.4affected · semver

Same product

progress: all records

Other highest-scoring records for the same primary product.

CVE-2023-42657WS_FTP Server Directory Traversal
43Plan
CVE-2008-0590Buffer overflow in Ipswitch WS_FTP Server with SSH 6.1.0.0 allows remote authenticated users to cause a denial of service (crash) and possib
43Plan
CVE-2001-1021Buffer overflows in WS_FTP 2.02 allow remote attackers to execute arbitrary code via long arguments to (1) DELE, (2) MDTM, (3) MLST, (4) MKD
43Plan

Published before and after this one in the same product

← EarlierCVE-2023-24029Feb 3, 2023 · In Progress WS_FTP Server before 8.8, it is possible for a host administrator to elevate their privileges via the administrative interface d
28Monitor
← EarlierCVE-2022-27665Apr 3, 2023 · Reflected XSS (via AngularJS sandbox escape expressions) exists in Progress Ipswitch WS_FTP Server 8.6.0.
34Monitor
Later →CVE-2023-40045Sep 27, 2023 · WS_FTP Server Ad Hoc Transfer Module Reflected Cross-Site Scripting Vulnerability
24Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
Progress Software Corporation WS_FTP Server	8.7.4	Vendor (CNA)
Progress Software Corporation WS_FTP Server	8.8.2	Vendor (CNA)

Exploit status

Weaponized

A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.

Evidence

Metasploit module ×1
Nuclei detection template ×1
Proof-of-concept repository on GitHub ×1

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
Source	Kind	Date
Metasploit module	exploit/windows/http/ws_ftp_rce_cve_2023_40044Progress Software WS_FTP Unauthenticated Remote Code Executionexploit	2023-09-27
Nuclei detection template	Nuclei template CVE-2023-40044	—
Proof-of-concept repository on GitHub	stars:1	2023-10-02

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

MetasploitSep 27, 2023same day
PublishedSep 27, 2023
First PoCOct 2, 2023+5 d
CISA KEVOct 5, 2023+8 d
TodayOct 30, 2026+1130 d

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Sean Yeoh - Assetnotefinder
Shubham Shah - Assetnotefinder

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

TR-23-0566 · Sep 29, 2023(WS_FTP Server Güvenlik Bildirimi)

All national notices →

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
A low-privileged account is enough.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Network
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-502 · Deserialization of Untrusted Data

CVSS vector

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

nvd-primary

Root cause

Data received over the network is deserialized into the language’s native object format without verifying its source. Code paths inside the object can be triggered during deserialization.

The bug in code

The whole CWE-502 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

python

1payload = sock.recv(65536)
2job = pickle.loads(payload)

Fixed

python

1payload = sock.recv(65536)
2if not hmac.compare_digest(sign(payload), header_sig):
3    raise PermissionError("invalid signature")
4job = JobSchema.validate(json.loads(payload))