XSS in Freescout-Help-Desk Freescout
CVE-2026-62854
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.
Vulnerability class: XSS (Cross-Site Scripting)
Published .
CVSS v3 metric
CVSS v3 base score 7.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Freescout-Help-Desk Freescout — versions < 1.8.225
Weakness classification (CWE)
References
- https://github.com/freescout-help-desk/freescout/commit/315ad05f73886649cb8bc2c014dd74b62cc28502
- https://github.com/freescout-help-desk/freescout/commit/7f6a5042c1326ceaf511f13982178dce036cedbe
- https://github.com/freescout-help-desk/freescout/releases/tag/1.8.225
- https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-jpq8-j69f-mj98
Frequently asked questions
- What is CVE-2026-62854?
- CVE-2026-62854 is a high-severity vulnerability in Freescout-Help-Desk Freescout, classified under Cross-site Scripting. CVSS score: 7.6/10. Published 2026-11-06.
- How severe is CVE-2026-62854?
- High severity. CVSS v3 base score is 7.6 out of 10.