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 t...

Description

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.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS 4.0

8.9/10

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/E:P/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 Probability

0.57%

42.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Freescout	Freescout	< 1.8.213

References

https://github.com/freescout-help-desk/freescout/commit/b1d6c2c601a6ec3626ab13e679607b5084dfbd38Patch
https://github.com/freescout-help-desk/freescout/releases/tag/1.8.213Release Notes
https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-5jw5-q9j7-4rxcExploit, Vendor Advisory
https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-5jw5-q9j7-4rxcExploit, Vendor Advisory

Timeline

Published: Apr 21, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is 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.

How severe is CVE-2026-40498?

CVE-2026-40498 has a CVSS score of 8.9/10 (HIGH severity). The EPSS model estimates a 0.57% probability of exploitation in the next 30 days.

How do I fix CVE-2026-40498?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.