CVE-2026-53593 (GCVE-0-2026-53593)

Vulnerability from cvelistv5 – Published: 2026-07-20 19:52 – Updated: 2026-07-21 14:56
VLAI
Title
FreeScout Vulnerable to Authenticated Remote Code Execution via incomplete upload extension denylist (.pht) — bypass of CVE-2025-48471
Summary
FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Prior to version 1.8.224, the denylist that neutralizes dangerous file uploads (`Helper::$restricted_extensions`) is incomplete: it does not cover the `.pht` extension. The authenticated upload endpoint `POST /uploads/upload` (`SecureController@upload`) stores files with their original extension into the web-accessible directory `storage/app/public/uploads/` (served at `/storage/uploads/`). On the standard Apache + `libapache2-mod-php` deployment, the default handler `<FilesMatch ".+\.ph(ar|p[3457]?|t|tml)$">` executes `.pht`, so **any authenticated agent can upload a `.pht` web shell and run arbitrary commands as the web-server user** (`www-data`). This is a direct bypass of the fix for CVE-2025-48471, which added `phtml`/`phar` but not `pht` (nor `phtm`, `phps`). Version 1.8.224 contains an updated fix.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-21 13:21 UTC
CWE
  • CWE-434 - Unrestricted Upload of File with Dangerous Type
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7974 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
freescout-help-desk freescout Affected: < 1.8.224
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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