Information disclosure in Freescout

CVE-2026-40498

FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.213, an unauthenticated attacker can access diagnostic and system tools that should be restricted to administrators. The /system/cron endpoint relies on a static MD5 hash derived from the APP_KEY, which is exposed in the response and logs. Accessing these endpoints reveals sensitive server information (Full Path Disclosure), process IDs, and allows for Resource Exhaustion (DoS) by triggering heavy background tasks repeatedly without any rate limiting. The cron hash is generated using md5(APP_KEY . 'web_cron_hash'). Since this hash is often transmitted via GET requests, it is susceptible to exposure in server logs, browser history, and proxy logs. Furthermore, the lack of rate limiting on these endpoints allows for automated resource exhaustion (DoS) and brute-force attempts. Version 1.8.213 fixes the issue.

Vulnerability class: Information Disclosure

EPSS: 0.006 (45.0th 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-2026-40498?
CVE-2026-40498 is a critical-severity vulnerability in Freescout, classified under Information Disclosure. CVSS score: 9.8/10. Published 2026-04-21.
How severe is CVE-2026-40498?
Critical severity. CVSS v3 base score is 9.8 out of 10.