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TI-2025-35979 Aliases CVE-2025-58163

FreeScout's deserialization of untrusted data can lead to Remote Code Execution

Priority MEDIUM 40CWE-502Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-502.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00721 54th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed freescout (freescout-help-desk): 1.8.186

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
freescout-help-deskfreescoutbefore 1.8.1861.8.186Patch availableCNA
  • freescout Vendorfreescout-help-desk Affected before 1.8.186 Fixed in 1.8.186 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:freescout:freescout:*:*:*:*:*:*:*:*before 1.8.186Vulnerablefreescout-help-desk
  • cpe:2.3:a:freescout:freescout:*:*:*:*:*:*:*:* Versions before 1.8.186 Vulnerable ·freescout-help-desk

Remediation

  • Fix · CNA freescout (freescout-help-desk) Fixed in 1.8.186

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-58163

References

Exploit 1

Patch 1

Other 1

  • TI-2026-22019 FreeScout's Predictable Authentication Token Enables Account Takeover CVSS 3.1CRITICAL 9.8
  • TI-2026-29249 FreeScout has Authentication Bypass and Information Disclosure in SystemController via /system/cron CVSS 4.0HIGH 8.9
  • TI-2026-29247 FreeScout has Predictable Attachment Token that Allows Unauthenticated Private File Download via Brute Force CVSS 4.0HIGH 8.8
  • TI-2026-25245 FreeScout: Stored XSS via Unescaped Email Template Rendering ({!! $thread->body !!}) CVSS 3.1CRITICAL 9.3
  • TI-2026-22596 FreeScout 1.8.206 Patch Bypass for CVE-2026-27636 via Zero-Width Space Character Leads to Remote Code Execution CVSS 3.1CRITICAL 10.0
  • TI-2024-19354 FreeScout OS Command Injection vulnerability CVSS 3.1CRITICAL 9.1
See all 45 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences