CVEvulnerability

CVE-2026-28289

8.1 HIGH Published 2026-03-03 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2026-03-03
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
10.0 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
CVSS 3.1 ([email protected])
8.1 HIGH — CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Weaknesses
CWE-434

Description

FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. A patch bypass vulnerability for CVE-2026-27636 in FreeScout 1.8.206 and earlier allows any authenticated user with file upload permissions to achieve Remote Code Execution (RCE) on the server by uploading a malicious .htaccess file using a zero-width space character prefix to bypass the security check. The vulnerability exists in the sanitizeUploadedFileName() function in app/Http/Helper.php. The function contains a Time-of-Check to Time-of-Use (TOCTOU) flaw where the dot-prefix check occurs before sanitization removes invisible characters. This vulnerability is fixed in 1.8.207.

Affected configurations

• freescout freescout (< 1.8.207)

Related

Weakness · CWE (1)

  • CWE-434 Unrestricted Upload of File with Dangerous Type weakness

References