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WhereIsIt Catalog file (.ctf)

.ctf file signature | application/octet-stream

WhereIsIt Catalog file

Safe

Magic Bytes

Offset 0
43 61 74 61 6C 6F 67 20 33 2E 30 30 00

Sources: Gary Kessler

Extension

.ctf

MIME Type

application/octet-stream

Byte Offset

0

Risk Level

Safe

Validation Code

How to validate .ctf files in Python

Python
def is_ctf(file_path: str) -> bool:
    """Check if file is a valid CTF by magic bytes."""
    signature = bytes([0x43, 0x61, 0x74, 0x61, 0x6C, 0x6F, 0x67, 0x20, 0x33, 0x2E, 0x30, 0x30, 0x00])
    with open(file_path, "rb") as f:
        return f.read(13) == signature

How to validate .ctf files in Node.js

Node.js
function isCTF(buffer: Buffer): boolean {
  const signature = Buffer.from([0x43, 0x61, 0x74, 0x61, 0x6C, 0x6F, 0x67, 0x20, 0x33, 0x2E, 0x30, 0x30, 0x00]);
  return buffer.subarray(0, 13).equals(signature);
}

How to validate .ctf files in Go

Go
func IsCTF(data []byte) bool {
    signature := []byte{0x43, 0x61, 0x74, 0x61, 0x6C, 0x6F, 0x67, 0x20, 0x33, 0x2E, 0x30, 0x30, 0x00}
    if len(data) < 13 {
        return false
    }
    return bytes.Equal(data[:13], signature)
}

API Endpoint

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

See the full API documentation for all endpoints and parameters.

Frequently Asked Questions

What is a .ctf file?

A .ctf file is a WhereIsIt Catalog file file. WhereIsIt Catalog file

What are the magic bytes for .ctf files?

The magic bytes for WhereIsIt Catalog file files are 43 61 74 61 6C 6F 67 20 33 2E 30 30 00 at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.

How do I validate a .ctf file?

To validate a .ctf file, read the first bytes of the file and compare them against the known magic bytes (43 61 74 61 6C 6F 67 20 33 2E 30 30 00) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.

What is the MIME type for .ctf files?

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

Is it safe to open .ctf files?

WhereIsIt Catalog file (.ctf) 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.