What is CVE-2020-19596?

CVE-2020-19596 is a critical-severity vulnerability in Coreftp Core FTP, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2021-04-05.

How severe is CVE-2020-19596?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Buffer overflow in Coreftp Core FTP

CVE-2020-19596

Buffer overflow vulnerability in Core FTP Server v1.2 Build 583, via a crafted username.

Vulnerability class: Buffer Overflow

Published 2021-04-05 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.013 (69.0th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 69th percentile — 69.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: 0.000

Affected products

Coreftp Core FTP — versions 1.2

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

References

www.0x90.zone/binary/reverse/exploitation/2020/08/16/CoreFTPServerRCE.html (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2020-19596?: CVE-2020-19596 is a critical-severity vulnerability in Coreftp Core FTP, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2021-04-05.
How severe is CVE-2020-19596?: Critical severity. CVSS v3 base score is 9.8 out of 10.