CVE-2026-53593
FreeScout Vulnerable to Authenticated Remote Code Execution via incomplete upload extension denylist (.pht) — bypass of CVE-2025-48471
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
8.8
FreeScout Vulnerable to Authenticated Remote Code Execution via incomplete upload extension denylist (.pht) — bypass of CVE-2025-48471
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.
- Record
CVE-2026-53593- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-434
- Updated
- 2026-11-02
EUVDEUVD-2026-46083
8.8
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.
- Record
EUVD-2026-46083- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
NVD
8.8
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.
- Record
CVE-2026-53593- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-434
- Updated
- 2026-11-02
OSV
8.8
FreeScout Vulnerable to Authenticated Remote Code Execution via incomplete upload extension denylist (.pht) — bypass of CVE-2025-48471
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.
- Record
CVE-2026-53593- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-434
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-53593 is a high vulnerability (CVSS 8.8) in Freescout-help-desk Freescout, published July 20, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.35%, the 29th percentile. No source names a fixed version.