CVE-2020-36941

Knockpy 4.1.1 contains a CSV injection vulnerability that allows attackers to inject malicious formulas into CSV reports through unfiltered server headers. Attackers can manipulate server response headers to include spreadsheet formulas that will execute when the CSV is opened in spreadsheet applications.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/guelfoweb/knock	Product
https://www.exploit-db.com/exploits/49342	Exploit Third Party Advisory
https://www.vulncheck.com/advisories/knockpy-csv-injection	Third Party Advisory
https://github.com/guelfoweb/knock	Product

Configurations

Configuration 1 (hide)

cpe:2.3:a:guelfoweb:knockpy:4.1.1:*:*:*:*:*:*:*

History

24 Mar 2026, 21:24

Type	Values Removed	Values Added
References	~~() https://github.com/guelfoweb/knock -~~	() https://github.com/guelfoweb/knock - Product
References	~~() https://www.exploit-db.com/exploits/49342 -~~	() https://www.exploit-db.com/exploits/49342 - Exploit, Third Party Advisory
References	~~() https://www.vulncheck.com/advisories/knockpy-csv-injection -~~	() https://www.vulncheck.com/advisories/knockpy-csv-injection - Third Party Advisory
CPE		cpe:2.3:a:guelfoweb:knockpy:4.1.1:::::::*
First Time		Guelfoweb knockpy Guelfoweb
Summary		(es) Knockpy 4.1.1 contiene una vulnerabilidad de inyección CSV que permite a los atacantes inyectar fórmulas maliciosas en informes CSV a través de encabezados de servidor sin filtrar. Los atacantes pueden manipular los encabezados de respuesta del servidor para incluir fórmulas de hoja de cálculo que se ejecutarán cuando el CSV se abra en aplicaciones de hoja de cálculo.

27 Jan 2026, 22:15

Type	Values Removed	Values Added
References	~~() https://github.com/guelfoweb/knock -~~	() https://github.com/guelfoweb/knock -

27 Jan 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-27 16:16

Updated : 2026-03-24 21:24

NVD link : CVE-2020-36941

Mitre link : CVE-2020-36941

CVE.ORG link : CVE-2020-36941

JSON object : View

Products Affected

guelfoweb

knockpy

CWE

CWE-1236

Improper Neutralization of Formula Elements in a CSV File

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