What is the CVSS score of CVE-2026-28289?

CVE-2026-28289 has a CVSS 3.1 base score of 10.0 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H. EPSS exploitation probability: 0.0%.

Which versions of PHP are affected by CVE-2026-28289?

FreeScout help desk systems are exposed to a critical remote code execution vulnerability (CVSS 10.0) that allows unauthenticated attackers to achieve complete system compromise.. A patch is available.

Is there a public PoC exploit available for CVE-2026-28289?

Yes, a public proof-of-concept exploit is available for CVE-2026-28289. Prioritise patching immediately. EPSS: 0.0%.

How to fix or mitigate CVE-2026-28289?

Within 24 hours: Inventory all FreeScout instances and assess external accessibility; apply vendor patch immediately to production systems or take affected systems offline if patching is not immediately possible. Within 7 days: Complete patching across all FreeScout deployments and verify patch installation through vulnerability scanning. Within 30 days: Conduct forensic analysis of access logs to identify potential breach activity and implement enhanced monitoring on help desk systems.

PHP CVE-2026-28289

CRITICAL

Unrestricted Upload of File with Dangerous Type (CWE-434)

2026-03-03 security-advisories@github.com

PHP Laravel RCE Race Condition Freescout

10.0

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

10.0 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 12, 2026 - 22:05 vuln.today

PoC Detected

Mar 11, 2026 - 19:29 vuln.today

Public exploit code

Patch released

Mar 11, 2026 - 19:29 nvd

Patch available

CVE Published

Mar 03, 2026 - 23:15 nvd

CRITICAL 10.0

DescriptionGitHub Advisory

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.