Skip to content

SO (.so)

.so file signature | application/octet-stream

Executable and Linkable Format[25]

Safe

Magic Bytes

Offset 10
23 20 54 68 69 73 20 69 73 20 61 20 73 68 65 6C 6C 20 61 72 63 68 69 76 65

Sources: Apache Tika

All Known Signatures

7 signature variants are documented for .so files across multiple sources.

Hex Signature Offset Sources
23 20 54 68 69 73 20 69 73 20 61 20 73 68 65 6C 6C 20 61 72 63 68 69 76 65 10 Apache Tika
1F 1E 0 Apache Tika
30 31 37 34 33 37 0 Apache Tika
1F FF 0 Apache Tika
FF 1F 0 Apache Tika
30 31 34 35 34 30 35 0 Apache Tika
7F 45 4C 46 0 Wikipedia

Extension

.so

MIME Type

application/octet-stream

Byte Offset

10

Risk Level

Safe

Validation Code

How to validate .so files in Python

Python 
def is_so(file_path: str) -> bool:
    """Check if file is a valid SO by magic bytes."""
    signature = bytes([0x23, 0x20, 0x54, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20, 0x61, 0x20, 0x73, 0x68, 0x65, 0x6C, 0x6C, 0x20, 0x61, 0x72, 0x63, 0x68, 0x69, 0x76, 0x65])
    with open(file_path, "rb") as f:
        return f.read(25) == signature

How to validate .so files in Node.js

Node.js 
function isSO(buffer: Buffer): boolean {
  const signature = Buffer.from([0x23, 0x20, 0x54, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20, 0x61, 0x20, 0x73, 0x68, 0x65, 0x6C, 0x6C, 0x20, 0x61, 0x72, 0x63, 0x68, 0x69, 0x76, 0x65]);
  return buffer.subarray(0, 25).equals(signature);
}

How to validate .so files in Go

Go 
func IsSO(data []byte) bool {
    signature := []byte{0x23, 0x20, 0x54, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20, 0x61, 0x20, 0x73, 0x68, 0x65, 0x6C, 0x6C, 0x20, 0x61, 0x72, 0x63, 0x68, 0x69, 0x76, 0x65}
    if len(data) < 25 {
        return false
    }
    return bytes.Equal(data[:25], signature)
}

API Endpoint

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

See the full API documentation for all endpoints and parameters.

Frequently Asked Questions

What is a .so file?

A .so file is a SO file. Executable and Linkable Format[25]

What are the magic bytes for .so files?

The magic bytes for SO files are 23 20 54 68 69 73 20 69 73 20 61 20 73 68 65 6C 6C 20 61 72 63 68 69 76 65 at byte offset 10. These bytes uniquely identify the file format regardless of the file extension.

How do I validate a .so file?

To validate a .so file, read the first bytes of the file and compare them against the known magic bytes (23 20 54 68 69 73 20 69 73 20 61 20 73 68 65 6C 6C 20 61 72 63 68 69 76 65) at offset 10. This is more reliable than checking the file extension alone, as extensions can be renamed.

What is the MIME type for .so files?

The primary MIME type for .so files is application/octet-stream.

Is it safe to open .so files?

SO (.so) 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.