high Known exploitedREV. 01
CVE-2023-40044WS_FTP Server — the transfer module that deserializes
The ad hoc transfer module in WS_FTP Server deserializes data it has not verified, so an attacker who never logged in runs commands on the host. Versions before 8.7.4 and 8.8.2 are affected, and ransomware crews used it.
Read the risk
THE VITAL STATS- CVSS score
- 8.8/ 10 CVSS v3.1
- EPSS probability
- 90% Likelihood of exploitation
- Attack complexity
- Low Conditions needed to exploit
- Known exploited
- Yes — CISA KEV
- CVE published
- 2023-09-27
- Added to KEV
- 2023-10-05
- Exploit published
- Yes
- Confidence
- high
- Kill chain
- initial access
- MITRE ATT&CK
- T1190
- Severity
- high
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attacker needsNetwork access to the transfer server.
Fixed inWS_FTP Server >= 8.7.4, WS_FTP Server >= 8.8.2
Behind the card
5 REFERENCES- 01CVE recordNVD recordnvd.nist.gov
- 02CISACISA Known Exploited Vulnerabilities catalogcisa.gov
- 03Vendor advisorycommunity.progress.comcommunity.progress.com
- 04Exploitpacketstormsecurity.compacketstormsecurity.com
- 05Exploitassetnote.ioassetnote.io
Field-level provenanceTRACE THE SOURCES +
Which source supports each field, when it was retrieved, and who extracted it.
| Fields | Source | Retrieved | Extractor | Confidence |
|---|---|---|---|---|
| cvss, exploitation.attack_complexity, exploitation.exploit_available, references, published_at | nvd.nist.gov | 2026-09-24 | scrty-crds-pipeline/0.1 | high |
| exploitation.known_exploited, exploitation.kev_added | cisa.gov | 2026-09-24 | scrty-crds-pipeline/0.1 | high |
| epss | api.first.org | 2026-09-24 | scrty-crds-pipeline/0.1 | high |
| title, summary, severity, remediation, mitre_attack, kill_chain, recommended_action, confidence, tags, exploitation.prerequisites | nvd.nist.gov | 2026-09-24 | claude-code | high |
Printing history
THE RECORD- r1Initial base card
First printing. This card has not been reprinted since publication.