Vulnerability in Guelfoweb Knock

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.

EPSS: 0.005 (39.6th percentile) — read the EPSS interpretation.

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.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-36941?
CVE-2020-36941 is a critical-severity vulnerability in Guelfoweb Knock, classified under Improper Neutralization of Formula Elements in a CSV File. CVSS score: 9.8/10. Published 2026-01-27.
How severe is CVE-2020-36941?
Critical severity. CVSS v3 base score is 9.8 out of 10.