Is this vulnerability remotely exploitable over the internet?

Yes. Any user who can reach the FreeScout web interface and authenticate with a role that permits file uploads can exploit this issue by uploading a specially named malicious file, without requiring direct server access.

Does exploitation require administrator or elevated privileges?

No. Administrator privileges are not strictly required. The core prerequisite is an authenticated account with file upload permissions, which may include lower-privileged roles if they are allowed to attach or upload files.

What is the safest general fix pattern for developers?

The most robust pattern is to normalize and sanitize filenames first, then perform security checks on that final, canonical value, and finally use that exact value when writing to disk. Combine this with a strict extension allowlist, storage outside the web root, and a policy that forbids any user-supplied configuration-like files.

Severity:

CRITICAL RISK

(10.0)

Unrestricted File Upload via TOCTOU Bypass (CWE-434) in FreeScout sanitizeUploadedFileName

CVE-2026-28289

Published:

Mar 3, 2026

Status:

Modified

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

NDV

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CRITICAL

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Remote Code Execution via SQL Injection on the Database Server

March 7, 2026

Vulnerability Type

Category:

Unrestricted File Upload

CWE:

CWE-434

Impact:

Remote Code Execution

Severity:

CRITICAL RISK

(10.0)

CVSS Version:

3.1

Vulnerability Type

Category:

Unrestricted File Upload

CWE:

CWE-434

Impact:

Remote Code Execution

Severity:

CRITICAL RISK

(10.0)

CVSS Version:

3.1

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Unrestricted File Upload via TOCTOU Bypass (CWE-434) in FreeScout sanitizeUploadedFileName

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

Recent Vulnerabilities

CRITICAL RISK

CRITICAL

(9.9)

Command Injection in MCP Stdio Configuration Validation (CWE-78) in WeKnora

CRITICAL RISK

CRITICAL

(9.9)

SQL Injection via PostgreSQL Array/Row Expressions (CWE-89) in WeKnora Query Engine

Vulnerability Type

Vulnerability Type

Vulnerability Type

Catch This CVE While Code Is Being Written

Ship clean & secure code faster

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