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VisualBASIC application magic bytes (.vbx)

.vbx file signature: 4D 5A | application/octet-stream

The VBX format is a Visual Basic application file associated with Microsoft Visual Basic, originally created and maintained by Microsoft. It is used to store executable program components and related resources for Windows applications built with Visual Basic. VBX files are legacy components from earlier versions of the platform and should be treated cautiously when obtained from untrusted sources, as they may contain executable code.

Safe

Magic Bytes

Offset 0
4D 5A

Sources: Gary Kessler

Extension

.vbx

MIME Type

application/octet-stream

Byte Offset

0

Risk Level

Safe

Validation Code

How to validate .vbx files in Python

Python 
def is_vbx(file_path: str) -> bool:
    """Check if file is a valid VBX by magic bytes."""
    signature = bytes([0x4D, 0x5A])
    with open(file_path, "rb") as f:
        return f.read(2) == signature

How to validate .vbx files in Node.js

Node.js 
function isVBX(buffer: Buffer): boolean {
  const signature = Buffer.from([0x4D, 0x5A]);
  return buffer.subarray(0, 2).equals(signature);
}

How to validate .vbx files in Go

Go 
func IsVBX(data []byte) bool {
    signature := []byte{0x4D, 0x5A}
    if len(data) < 2 {
        return false
    }
    return bytes.Equal(data[:2], signature)
}

API Endpoint

GET /api/v1/vbx
curl https://filesignature.org/api/v1/vbx

See the full API documentation for all endpoints and parameters.

Frequently Asked Questions

What is a .vbx file?

A .vbx file is a VisualBASIC application file. The VBX format is a Visual Basic application file associated with Microsoft Visual Basic, originally created and maintained by Microsoft. It is used to store executable program components and related resources for Windows applications built with Visual Basic. VBX files are legacy components from earlier versions of the platform and should be treated cautiously when obtained from untrusted sources, as they may contain executable code.

What are the magic bytes for .vbx files?

The magic bytes for VisualBASIC application (.vbx) files are 4D 5A at byte offset 0. These bytes identify the file format more reliably than the extension alone.

How do I validate a .vbx file?

To validate a .vbx file, read the first bytes of the file and compare them against the known magic bytes (4D 5A) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.

What is the MIME type for .vbx files?

There is no officially registered MIME type for .vbx files. Systems typically use application/octet-stream as a generic fallback when handling this format.

Is it safe to open .vbx files?

VisualBASIC application (.vbx) files are generally safe to open. They are classified as low risk because they primarily contain data rather than executable code. However, always ensure files come from a trusted source.