FreeScout's deserialization of untrusted data leads to Remote Code Execution
Published Jul 26, 2025
8.6
HIGHCVSS 4.0
EPSS 0.98%
Description
FreeScout is a lightweight free open source help desk and shared inbox built with PHP (Laravel framework). In versions 1.8.185 and below, there is a critical deserialization vulnerability in the /conversation/ajax endpoint that allows authenticated users with knowledge of the APP_KEY to achieve remote code execution. The vulnerability occurs when the application processes the attachments_all and attachments POST parameters through the insecure Helper::decrypt() function, which performs unsafe deserialization of user-controlled data without proper validation. This flaw enables attackers to create arbitrary objects and manipulate their properties, leading to complete compromise of the web application. This is fixed in version 1.8.186.
Affected products
-
- Version < 1.8.186StatusaffectedConstraints-
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Freescout-Help-Desk | Freescout | n/a |
|
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
1 other source (NVD) ▾
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/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
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
PoCAutomatable
NoTechnical Impact
PartialDecision
n/aAssessed Jul 28, 2025 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 3, 2026.
Score over time
2025–2026- EPSS v4
- EPSS v5
Percentile over time
- EPSS v4
- EPSS v5
Table of values (7 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 3, 2026 | 0.98% (0.00978) | 60.86th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.94% (0.00937) | 56.04th | v5 (v2026.06.15) |
| May 22, 2026 | 6.60% (0.06597) | 91.28th | v4 (v2025.03.14) |
| Apr 11, 2026 | 3.84% (0.03842) | 88.19th | v4 (v2025.03.14) |
| Feb 19, 2026 | 2.83% (0.02833) | 85.89th | v4 (v2025.03.14) |
| Nov 25, 2025 | 1.68% (0.01679) | 81.60th | v4 (v2025.03.14) |
| Jul 26, 2025 | 0.49% (0.00490) | 64.55th | v4 (v2025.03.14) |
References (2)
- https://github.com/freescout-help-desk/freescout/commit/9669c57f1ddbee896752d9e16270abfd97b20eb9 x_refsource_MISCPatch
- https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-vcc2-6r66-gvvj x_refsource_CONFIRMExploitVendor Advisory
| Link | Providers | Tags |
|---|---|---|
| https://github.com/freescout-help-desk/freescout/commit/9669c57f1ddbee896752d9e16270abfd97b20eb9 | x_refsource_MISCPatch | |
| https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-vcc2-6r66-gvvj | x_refsource_CONFIRMExploitVendor Advisory |
Change history (0)
No recorded changes yet.