What is CVE-2026-40590?

CVE-2026-40590 is a medium-severity vulnerability in Freescout-help-desk Freescout, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 4.3/10. Published 2026-04-21.

How severe is CVE-2026-40590?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Auth bypass in Freescout-help-desk Freescout

CVE-2026-40590

FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.214, the Change Customer modal exposes a “Create a new customer” flow via POST /customers/ajax with action=create. Under limited visibility, the endpoint dr…

Vulnerability class: IDOR (Insecure Direct Object Reference)

EPSS: 0.002 (11.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N.

Affected products

Freescout-help-desk Freescout — versions < 1.8.214

Weakness classification (CWE)

CWE-639 — Authorization Bypass Through User-Controlled Key

References

security-advisories@github.com (x_refsource_CONFIRM)
security-advisories@github.com (x_refsource_MISC)
security-advisories@github.com (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-40590?: CVE-2026-40590 is a medium-severity vulnerability in Freescout-help-desk Freescout, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 4.3/10. Published 2026-04-21.
How severe is CVE-2026-40590?: Medium severity. CVSS v3 base score is 4.3 out of 10.