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FreescoutApplication

CVE-2026-40498

CRITICAL · 9.8 CVSS v3.1 Published 2026-04-21
Fix available
A fix is available. Upgrade to 1.8.213 or later.
See remediation →
100/100
Remediation priority · Urgent
Public exploit Remotely reachable No privileges Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

FreeScout versions before 1.8.213 have an authentication bypass vulnerability where the /system/cron endpoint uses a static MD5 hash derived from the APP_KEY (md5(APP_KEY . 'web_cron_hash')) to protect access. Since this hash is transmitted via GET requests, it gets logged in server logs, browser history, and proxy logs, allowing unauthenticated attackers to access admin-only diagnostic tools. Additionally, the lack of rate limiting enables resource exhaustion attacks and exposes sensitive information including full server paths and process IDs.

MitigationUpgrade to FreeScout version 1.8.213 or later, and rotate the APP_KEY immediately since it may have been exposed in logs. Implement rate limiting on all system endpoints as a defense-in-depth measure.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
FreescoutApplication
Affected:< 1.8.213

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify FreeScout version
    Locate the version file or check the admin dashboard for the installed FreeScout version number. Common locations include the footer of admin pages or a /about endpoint.
    Affected if The installed version is below 1.8.213 (e.g., 1.8.212, 1.8.200, etc.)
  2. Verify /system/cron endpoint accessibility
    Send a GET request to /system/cron with no authentication headers. Observe whether the endpoint responds without requiring login credentials.
    Affected if The endpoint returns a response (diagnostic data, cron output, or any server information) without redirecting to a login page or requiring authentication.
  3. Inspect server and proxy logs for cron hash exposure
    Search access logs (Apache, Nginx, reverse proxy logs) for requests to /system/cron containing the web_cron_hash parameter. Check for patterns like 'web_cron_hash=' in log files.
    Affected if Requests to /system/cron with the hash parameter are present in logs, indicating the static hash was transmitted via GET and recorded.
  4. Confirm APP_KEY rotation status
    Check the .env file for APP_KEY. If previously compromised, the key should have been rotated after patching. Compare current key to any known or suspected exposed versions.
    Affected if The APP_KEY has not been rotated since the vulnerability was disclosed, or the same APP_KEY used during the vulnerable period is still in use.

You are affected if FreeScout version is below 1.8.213 and the /system/cron endpoint responds without authentication, especially if the hash appears in server logs.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 1.8.213 or later
Fixed in 1.8.213
Vendor patch github.com →
Interim mitigation

Upgrade to FreeScout version 1.8.213 or later, and rotate the APP_KEY immediately since it may have been exposed in logs. Implement rate limiting on all system endpoints as a defense-in-depth measure.

Recommended fix High confidence

FreeScout 1.8.213

  1. Backup your FreeScout installation and database before upgrading
  2. Download and install FreeScout version 1.8.213 or later from the official repository
  3. After upgrading, regenerate the APP_KEY to ensure the compromised hash is no longer valid
  4. Verify that the /system/cron endpoint now properly authenticates requests
  5. Review server logs for any signs of exploitation attempts using the old hash

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Freescout Scoped from the published advisory
  • Consultation4.0 h
  • Implementation6.0 h
  • Testing4.0 h
  • Review / QA2.0 h
16.0 hours of engineering $2,840
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,544.

Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-40498 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data