How severe is CVE-2023-40044?

CVE-2023-40044 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-40044 being actively exploited?

Yes. CVE-2023-40044 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2023-10-05, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2023-40044?

CVE-2023-40044 affects Progress Ws Ftp Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-40044?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2023-40044 have an EU (EUVD) identifier?

Yes. CVE-2023-40044 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-44651. It is also flagged as exploited in the EUVD (since 2023-10-05).

When was CVE-2023-40044 published?

CVE-2023-40044 was published on 2023-09-27 and last updated on 2026-06-17.

CVE-2023-40044

CVE-2023-40044 is a critical-severity vulnerability in Progress Ws Ftp Server with a CVSS 3.x base score of 10.0. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2023-10-05). The underlying weakness is classified as CWE-502.

Key facts

Severity: Critical (CVSS 3.x base score 10.0)
EPSS exploit prediction: 90% (100th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2023-10-05)
EU (EUVD) id: EUVD-2023-44651
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2023-10-05)
Weakness: CWE-502
Affected product: Progress Ws Ftp Server
Published: 2023-09-27
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2023-40044?: 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.
How severe is CVE-2023-40044?: CVE-2023-40044 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-40044 being actively exploited?: Yes. CVE-2023-40044 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2023-10-05, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2023-40044?: CVE-2023-40044 affects Progress Ws Ftp Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-40044?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2023-40044 have an EU (EUVD) identifier?: Yes. CVE-2023-40044 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-44651. It is also flagged as exploited in the EUVD (since 2023-10-05).
When was CVE-2023-40044 published?: CVE-2023-40044 was published on 2023-09-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:progress:ws_ftp_server:*:*:*:*:*:*:*:*

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