---
id: CVE-2026-62854
title: 'FreeScout: Stored XSS in mailbox signature via same-origin JS upload'
summary: >-
  FreeScout is a self-hosted help desk and shared mailbox. Prior to 1.8.225, a
  user who can edit a mailbox signature can combine a scriptable file uploaded
  through /uploads/upload with nested tag fragments that bypass
  Helper::stripDangerou…
severity: high
cvss: 7.6
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N'
cvssSource: cna
cwe:
  - CWE-79
vendor: freescout-help-desk
product: freescout
affected:
  - freescout < 1.8.225
published: '2026-11-06'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T16:50:58.184Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-62854'
references:
  - url: >-
      https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-jpq8-j69f-mj98
    label: >-
      https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-jpq8-j69f-mj98
  - url: >-
      https://github.com/freescout-help-desk/freescout/commit/315ad05f73886649cb8bc2c014dd74b62cc28502
    label: >-
      https://github.com/freescout-help-desk/freescout/commit/315ad05f73886649cb8bc2c014dd74b62cc28502
  - url: >-
      https://github.com/freescout-help-desk/freescout/commit/7f6a5042c1326ceaf511f13982178dce036cedbe
    label: >-
      https://github.com/freescout-help-desk/freescout/commit/7f6a5042c1326ceaf511f13982178dce036cedbe
  - url: 'https://github.com/freescout-help-desk/freescout/releases/tag/1.8.225'
    label: 'https://github.com/freescout-help-desk/freescout/releases/tag/1.8.225'
tags:
  - cve.org
ingestedAt: '2026-11-06T18:00:12.621Z'
epss: 0.00215
epssPercentile: 0.11888
---

## Overview

FreeScout is a self-hosted help desk and shared mailbox. Prior to 1.8.225, a user who can edit a mailbox signature can combine a scriptable file uploaded through /uploads/upload with nested tag fragments that bypass Helper::stripDangerousTags(). The resulting external script is served from the same origin, so the script-src 'self' policy permits it when another user opens the affected mailbox reply editor or new-ticket page. The script executes with the victim's FreeScout privileges and can read visible data and perform same-origin actions. This issue is fixed in version 1.8.225.

## Affected

- `freescout < 1.8.225`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.