CVE-2025-58163
HighCVSS 8.8Exploitation Probability (EPSS)
Elevated risk53th percentile - higher than 53% of all known CVEs
Summary
FreeScout versions 1.8.185 and earlier contain a deserialization of untrusted data vulnerability that allows authenticated attackers with knowledge of the application's APP_KEY to achieve remote code execution. The vulnerability is exploited via the endpoint /help/{mailbox_id}/auth/{customer_id}/{hash}/{timestamp}, where customer_id and timestamp parameters are processed through the decrypt function in app/Helper.php without proper validation, leading to deserialization of malicious PHP objects.
Risk Assessment
An attacker with a valid account and knowledge of the APP_KEY can execute arbitrary commands on the server, taking control of the help desk system and accessing data.
Recommendation
Update FreeScout to version 1.8.186 or later, which fixes the vulnerability.
Other vulnerabilities in FreeScout
See all- CVE-2026-41906High
FreeScout is a free help desk and shared inbox built with the Laravel framework. Prior to version 1.8.214, the Change Customer modal correctly hides out-of-scope customers, but the backend conversation_change_customer action accepts any supplied customer_email.
- CVE-2026-41905High
FreeScout prior to version 1.8.217 had a vulnerability in the Helper::sanitizeRemoteUrl() function that improperly validated URLs after HTTP redirects. An attacker could exploit this vulnerability to redirect traffic to internal HTTP services that would normally be blocked.
- CVE-2026-41904High
FreeScout prior to version 1.8.217 allows users with updateAutoReply permission to store an XSS payload in the auto-reply message. The payload is rendered unescaped in the auto-reply email sent to customers.
- CVE-2026-53595Critical
In FreeScout before version 1.8.224, the public endpoint `POST /user-setup/{hash}/{invite_sent_at}` allows an attacker to take over a user account without authentication. The vulnerability is due to trailing space equality in MySQL/MariaDB VARCHAR and improper decryption of the `invite_sent_at` parameter.
- CVE-2026-41902Critical
FreeScout prior to version 1.8.217 has a vulnerability in the /user-setup/{hash} endpoint that accepts a 60-character random invite_hash to set a new user's password. The lack of expiration check allows for unauthorized account takeover long after the invite was issued.
- CVE-2026-107393Medium
In FreeScout prior to 1.8.235, when APP_CLOUDFLARE_IS_USED is enabled, FreeScout trusts an unvalidated CF-Connecting-IP header during failed login attempts and stores the spoofed value in the activity log. LogsMonitor inserts the value into an administrator alert email without HTML escaping, allowing injected HTML to execute when an administrator opens the email.
- CVE-2026-53596Medium
FreeScout, a free help desk built with Laravel, does not enforce rate limiting on the file upload endpoint. Any user can flood the server with upload requests, leading to database overload and potential denial of service for all users. Version 1.8.224 contains a fix.
- CVE-2026-53594Medium
FreeScout prior to version 1.8.224 has a vulnerability in the App Logs feature that allows an authenticated attacker to download arbitrary server-local files readable by the PHP process via manipulation of the dl parameter.
- CVE-2026-53593High
FreeScout before version 1.8.224 has an incomplete denylist of dangerous file extensions, missing the .pht extension. An authenticated agent can upload a .pht web shell, leading to remote code execution on the web server.
- CVE-2026-53592Medium
A Prototype Pollution vulnerability in the getQueryParam function in /public/js/main.js in FreeScout. The fix in version 1.8.139 is incomplete, allowing attacks via nested URL keys. Fixed in version 1.8.223.
Original NVD description (English source)
FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Versions 1.8.185 and earlier contain a deserialization of untrusted data vulnerability that allows authenticated attackers with knowledge of the application's APP_KEY to achieve remote code execution. The vulnerability is exploited via endpoint, e.g.: `/help/{mailbox_id}/auth/{customer_id}/{hash}/{timestamp}` where the `customer_id` and `timestamp` parameters are processed through the decrypt function in `app/Helper.php` without proper validation. The code decrypts using Laravel's built-in encryption functions, which subsequently deserialize the decrypted payload without sanitization, allowing attackers to craft malicious serialized PHP objects using classes to trigger arbitrary command execution. This is fixed in version 1.8.186.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS