Cyber Resilience

CVE-2020-37155

MediumPublic PoC

Published: 07 February 2026

Published
07 February 2026
Modified
15 April 2026
KEV Added
Patch
CVSS Score v4 6.7 CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0002 3.7th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2020-37155 is a medium-severity Classic Buffer Overflow (CWE-120) vulnerability in Coreftp (inferred from references). Its CVSS base score is 6.7 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 3.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).

Deeper analysis

CVE-2020-37155 is a buffer overflow vulnerability in Core FTP Lite version 1.3, specifically within the username input field. The issue enables attackers to crash the application by supplying oversized input, such as a 7000-byte payload of repeated 'A' characters, without requiring further interaction. It is classified under CWE-120 and carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

The vulnerability can be exploited by unauthenticated attackers over the network with low attack complexity and no user interaction. Exploitation leads to a denial-of-service condition by crashing the affected FTP application, disrupting service availability while causing no impact to confidentiality or integrity.

Proof-of-concept exploits and advisories document the issue, including an entry on Exploit-DB at https://www.exploit-db.com/exploits/48100 and a denial-of-service PoC advisory from VulnCheck at https://www.vulncheck.com/advisories/core-ftp-lite-denial-of-service-poc. The vendor's site is available at http://www.coreftp.com/. No patch or specific mitigation steps are detailed in the CVE information.

EU & UK References

Vulnerability details

Core FTP Lite 1.3 contains a buffer overflow vulnerability in the username input field that allows attackers to crash the application by supplying oversized input. Attackers can generate a 7000-byte payload of repeated 'A' characters to trigger an application crash…

more

without requiring additional interaction.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Why these techniques?

Buffer overflow in network-accessible FTP application input directly enables application exploitation resulting in denial-of-service crash (T1499.004).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

CVEs Like This One

CVE-2025-20115Shared CWE-120
CVE-2020-37205Shared CWE-120
CVE-2026-28875Shared CWE-120
CVE-2020-37194Shared CWE-120
CVE-2020-37180Shared CWE-120
CVE-2024-24419Shared CWE-120
CVE-2019-25353Shared CWE-120
CVE-2026-30075Shared CWE-120
CVE-2020-37213Shared CWE-120
CVE-2021-47798Shared CWE-120

Affected Assets

Coreftp
inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly requires validation of username input length/format to reject oversized payloads before they reach the vulnerable buffer in Core FTP Lite.

prevent

Applies memory-protection mechanisms (e.g., ASLR, DEP, stack canaries) that can prevent or contain the buffer-overflow crash triggered by the 7000-byte username.

prevent

Mandates timely remediation (patch, upgrade, or replacement) of the known buffer-overflow flaw in the unauthenticated FTP username handler.

References