[MASWE-0020] Weak Encryption (by @appknox) (#2910)

* added weaknesss

* updated weakness

* added MASTG-DEMO, rule, MASTG-TEST

* updated weakness.md

* fix spelling

* Update weaknesses/MASVS-CRYPTO/MASWE-0020.md

* Update weaknesses/MASVS-CRYPTO/MASWE-0020.md

* Update weaknesses/MASVS-CRYPTO/MASWE-0020.md

* Update weaknesses/MASVS-CRYPTO/MASWE-0020.md

* Update weaknesses/MASVS-CRYPTO/MASWE-0020.md

* Update weaknesses/MASVS-CRYPTO/MASWE-0020.md

* removed duplicate

* change status to new

* updated title MASTG-TEST-0211.md

* updated title MASTG-DEMO-0016.md

* updated tests-beta

* fix lint

* updated MASWE-0020.md

* updated mitigations

* updated changes

* removed MASTG-TEST-0211.md

* added new Demo

* 2 demo added

* renamed semgrep files

* updated

* rename

* updated

* updated MASWE-0020.md

* updated MASWE-0020.md

* updated weak-encryption.yaml

* Renamed files

* updated Demo.md

* rename rules filename

* updated changes

* updated changes

* fix

---------

Co-authored-by: Sven <sven@bsddaemon.org>

demos/android/MASVS-CRYPTO/MASTG-DEMO-0022/MASTG-DEMO-0022.md

@@ -0,0 +1,33 @@
+---
+platform: android
+title: Uses of Insecure Encryption Algorithms in Cipher with semgrep
+id: MASTG-DEMO-0022
+code: [kotlin]
+---
+
+### Sample
+
+The code snippet below shows sample code contains use of insecure encryption algorithms.
+
+{{ MastgTest.kt # MastgTest_reversed.java }}
+
+### Steps
+
+Let's run our @MASTG-TOOL-0110 rule against the sample code.
+
+{{ ../../../../rules/mastg-android-weak-encryption-algorithms.yaml }}
+
+{{ run.sh }}
+
+### Observation
+
+The rule has identified two instances in the code file where an insecure encryption is used. The specified line numbers are from the reversed code for further investigation and remediation.
+
+{{ output.txt }}
+
+### Evaluation
+
+The test fails since several instances of weak encryption algorithms were found:
+
+- Line 36 utilize insecure DES algorithm.
+- Line 59 utilize insecure 3DES algorithm.

demos/android/MASVS-CRYPTO/MASTG-DEMO-0022/MastgTest.kt

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+package org.owasp.mastestapp
+
+import android.content.Context
+import java.security.Key
+import javax.crypto.Cipher
+import javax.crypto.SecretKeyFactory
+import javax.crypto.spec.DESKeySpec
+import javax.crypto.spec.DESedeKeySpec
+import javax.crypto.spec.SecretKeySpec
+import android.util.Base64
+
+class MastgTest(private val context: Context) {
+
+    // Vulnerable encryption using DES (weak algorithm)
+    fun vulnerableDesEncryption(data: String): String {
+        try {
+            // Weak key for DES
+            val keySpec = DESKeySpec("12345678".toByteArray())
+            val keyFactory = SecretKeyFactory.getInstance("DES")
+            val secretKey: Key = keyFactory.generateSecret(keySpec)
+
+            // Weak encryption algorithm (DES) and weak mode (ECB)
+            val cipher = Cipher.getInstance("DES")
+            cipher.init(Cipher.ENCRYPT_MODE, secretKey)
+
+            val encryptedData = cipher.doFinal(data.toByteArray())
+            return Base64.encodeToString(encryptedData, Base64.DEFAULT)
+        } catch (e: Exception) {
+            return "Encryption error: ${e.message}"
+        }
+    }
+
+
+    // Vulnerable encryption using 3DES (Triple DES)
+    fun vulnerable3DesEncryption(data: String): String {
+        try {
+            // Weak key for 3DES (24-byte key)
+            val keySpec = DESedeKeySpec("123456789012345678901234".toByteArray()) // 24 bytes key
+            val keyFactory = SecretKeyFactory.getInstance("DESede")
+            val secretKey: Key = keyFactory.generateSecret(keySpec)
+
+            // Weak encryption algorithm (3DES)
+            val cipher = Cipher.getInstance("DESede")
+            cipher.init(Cipher.ENCRYPT_MODE, secretKey)
+
+            val encryptedData = cipher.doFinal(data.toByteArray())
+            return Base64.encodeToString(encryptedData, Base64.DEFAULT)
+        } catch (e: Exception) {
+            return "Encryption error: ${e.message}"
+        }
+    }
+
+    fun mastgTest(): String {
+        val sensitiveString = "Hello from the OWASP MASTG Test app."
+
+        // Encrypt with weak DES
+        val desEncryptedString = vulnerableDesEncryption(sensitiveString)
+
+        // Encrypt with weak 3DES
+        val tripleDesEncryptedString = vulnerable3DesEncryption(sensitiveString)
+
+        // Returning the encrypted results
+        return "DES Encrypted: $desEncryptedString\n3DES Encrypted: $tripleDesEncryptedString"
+    }
+}

demos/android/MASVS-CRYPTO/MASTG-DEMO-0022/MastgTest_reversed.java

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+package org.owasp.mastestapp;
+
+import android.content.Context;
+import android.util.Base64;
+import java.security.Key;
+import javax.crypto.Cipher;
+import javax.crypto.SecretKeyFactory;
+import javax.crypto.spec.DESKeySpec;
+import javax.crypto.spec.DESedeKeySpec;
+import kotlin.Metadata;
+import kotlin.jvm.internal.Intrinsics;
+import kotlin.text.Charsets;
+
+/* compiled from: MastgTest.kt */
+@Metadata(d1 = {"\u0000\u001a\n\u0002\u0018\u0002\n\u0002\u0010\u0000\n\u0000\n\u0002\u0018\u0002\n\u0002\b\u0002\n\u0002\u0010\u000e\n\u0002\b\u0004\b\u0007\u0018\u00002\u00020\u0001B\r\u0012\u0006\u0010\u0002\u001a\u00020\u0003¢\u0006\u0002\u0010\u0004J\u0006\u0010\u0005\u001a\u00020\u0006J\u000e\u0010\u0007\u001a\u00020\u00062\u0006\u0010\b\u001a\u00020\u0006J\u000e\u0010\t\u001a\u00020\u00062\u0006\u0010\b\u001a\u00020\u0006R\u000e\u0010\u0002\u001a\u00020\u0003X\u0082\u0004¢\u0006\u0002\n\u0000¨\u0006\n"}, d2 = {"Lorg/owasp/mastestapp/MastgTest;", "", "context", "Landroid/content/Context;", "(Landroid/content/Context;)V", "mastgTest", "", "vulnerable3DesEncryption", "data", "vulnerableDesEncryption", "app_debug"}, k = 1, mv = {1, 9, 0}, xi = 48)
+/* loaded from: classes4.dex */
+public final class MastgTest {
+    public static final int $stable = 8;
+    private final Context context;
+
+    public MastgTest(Context context) {
+        Intrinsics.checkNotNullParameter(context, "context");
+        this.context = context;
+    }
+
+    public final String vulnerableDesEncryption(String data) {
+        Intrinsics.checkNotNullParameter(data, "data");
+        try {
+            byte[] bytes = "12345678".getBytes(Charsets.UTF_8);
+            Intrinsics.checkNotNullExpressionValue(bytes, "this as java.lang.String).getBytes(charset)");
+            DESKeySpec keySpec = new DESKeySpec(bytes);
+            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
+            Key generateSecret = keyFactory.generateSecret(keySpec);
+            Intrinsics.checkNotNullExpressionValue(generateSecret, "generateSecret(...)");
+            Key secretKey = generateSecret;
+            Cipher cipher = Cipher.getInstance("DES");
+            cipher.init(1, secretKey);
+            byte[] bytes2 = data.getBytes(Charsets.UTF_8);
+            Intrinsics.checkNotNullExpressionValue(bytes2, "this as java.lang.String).getBytes(charset)");
+            byte[] encryptedData = cipher.doFinal(bytes2);
+            String encodeToString = Base64.encodeToString(encryptedData, 0);
+            Intrinsics.checkNotNullExpressionValue(encodeToString, "encodeToString(...)");
+            return encodeToString;
+        } catch (Exception e) {
+            return "Encryption error: " + e.getMessage();
+        }
+    }
+
+    public final String vulnerable3DesEncryption(String data) {
+        Intrinsics.checkNotNullParameter(data, "data");
+        try {
+            byte[] bytes = "123456789012345678901234".getBytes(Charsets.UTF_8);
+            Intrinsics.checkNotNullExpressionValue(bytes, "this as java.lang.String).getBytes(charset)");
+            DESedeKeySpec keySpec = new DESedeKeySpec(bytes);
+            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DESede");
+            Key generateSecret = keyFactory.generateSecret(keySpec);
+            Intrinsics.checkNotNullExpressionValue(generateSecret, "generateSecret(...)");
+            Key secretKey = generateSecret;
+            Cipher cipher = Cipher.getInstance("DESede");
+            cipher.init(1, secretKey);
+            byte[] bytes2 = data.getBytes(Charsets.UTF_8);
+            Intrinsics.checkNotNullExpressionValue(bytes2, "this as java.lang.String).getBytes(charset)");
+            byte[] encryptedData = cipher.doFinal(bytes2);
+            String encodeToString = Base64.encodeToString(encryptedData, 0);
+            Intrinsics.checkNotNullExpressionValue(encodeToString, "encodeToString(...)");
+            return encodeToString;
+        } catch (Exception e) {
+            return "Encryption error: " + e.getMessage();
+        }
+    }
+
+    public final String mastgTest() {
+        String desEncryptedString = vulnerableDesEncryption("Hello from the OWASP MASTG Test app.");
+        String tripleDesEncryptedString = vulnerable3DesEncryption("Hello from the OWASP MASTG Test app.");
+        return "DES Encrypted: " + desEncryptedString + "\n3DES Encrypted: " + tripleDesEncryptedString;
+    }
+}

demos/android/MASVS-CRYPTO/MASTG-DEMO-0022/output.txt

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+
+
+┌─────────────────┐
+│ 2 Code Findings │
+└─────────────────┘
+
+    MastgTest_reversed.java
+    ❯❱rules.weak-encryption-algorithms
+          [MASVS-CRYPTO-1] Weak encryption algorithms found in use.
+
+           36┆ Cipher cipher = Cipher.getInstance("DES");
+            ⋮┆----------------------------------------
+           59┆ Cipher cipher = Cipher.getInstance("DESede");

demos/android/MASVS-CRYPTO/MASTG-DEMO-0022/run.sh

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+NO_COLOR=true semgrep -c ../../../../rules/mastg-android-weak-encryption-algorithms.yaml ./MastgTest_reversed.java --text -o output.txt

demos/android/MASVS-CRYPTO/MASTG_DEMO-0016/MASTG-DEMO-0016.md

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+---
+platform: android
+title: Uses of Insecure Encryption Modes in Cipher with semgrep
+id: MASTG-DEMO-0016
+code: [kotlin]
+test: MASTG-TEST-0221
+---
+
+### Sample
+
+The code snippet below shows sample code contains use of insecure encryption modes.
+
+{{ MastgTest.kt # MastgTest_reversed.java }}
+
+### Steps
+
+Let's run our @MASTG-TOOL-0110 rule against the sample code.
+
+{{ ../../../../rules/mastg-android-weak-encryption-modes }}
+
+{{ run.sh }}
+
+### Observation
+
+The rule has identified six instances in the code file, where insecure encryption modes are used.
+
+{{ output.txt }}
+
+### Evaluation
+
+The test fails since the output contains several instances of the ECB mode of AES:
+
+- Line 36 using Cipher.getInstance("AES") defaults to ECB.
+- Line 55 using Cipher.getInstance("AES/ECB/NoPadding");.
+- Line 76 using Cipher.getInstance("AES/ECB/PKCS5Padding");.
+- Line 95 using Cipher.getInstance("AES/ECB/ISO10126Padding");.
+- Line 118 using Cipher.getInstance("DES/ECB/PKCS5Padding");.
+- Line 141 using Cipher.getInstance("DESede/ECB/PKCS5Padding");.

demos/android/MASVS-CRYPTO/MASTG_DEMO-0016/MastgTest.kt

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+package org.owasp.mastestapp
+
+import android.content.Context
+import java.security.Key
+import javax.crypto.Cipher
+import javax.crypto.SecretKeyFactory
+import javax.crypto.spec.DESKeySpec
+import javax.crypto.spec.DESedeKeySpec
+import javax.crypto.spec.SecretKeySpec
+import android.util.Base64
+
+class MastgTest(private val context: Context) {
+
+    // Vulnerable AES encryption
+    fun vulnerableAesEncryption(data: String): String {
+        try {
+            val key = "1234567890123456".toByteArray() // 16 bytes key for AES
+            val secretKeySpec = SecretKeySpec(key, "AES")
+
+            // Default mode for AES (ECB)
+            val cipher = Cipher.getInstance("AES")
+            cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec)
+
+            val encryptedData = cipher.doFinal(data.toByteArray())
+            return Base64.encodeToString(encryptedData, Base64.DEFAULT)
+        } catch (e: Exception) {
+            return "Encryption error: ${e.message}"
+        }
+    }
+
+    // Vulnerable AES with ECB and NoPadding (manual padding applied)
+    fun vulnerableAesEcbNoPadding(data: String): String {
+        try {
+            val key = "1234567890123456".toByteArray()
+            val secretKeySpec = SecretKeySpec(key, "AES")
+
+            val cipher = Cipher.getInstance("AES/ECB/NoPadding")
+            cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec)
+
+            // Ensure the data is padded to match the block size
+            val blockSize = 16
+            val paddingLength = blockSize - (data.length % blockSize)
+            val paddedData = data + "\u0000".repeat(paddingLength) // Null padding
+
+            val encryptedData = cipher.doFinal(paddedData.toByteArray())
+            return Base64.encodeToString(encryptedData, Base64.DEFAULT).trim()
+        } catch (e: Exception) {
+            return "Encryption error: ${e.message}"
+        }
+    }
+
+    // Vulnerable AES with ECB and PKCS5Padding
+    fun vulnerableAesEcbPkcs5Padding(data: String): String {
+        try {
+            val key = "1234567890123456".toByteArray()
+            val secretKeySpec = SecretKeySpec(key, "AES")
+
+            val cipher = Cipher.getInstance("AES/ECB/PKCS5Padding")
+            cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec)
+
+            val encryptedData = cipher.doFinal(data.toByteArray())
+            return Base64.encodeToString(encryptedData, Base64.DEFAULT)
+        } catch (e: Exception) {
+            return "Encryption error: ${e.message}"
+        }
+    }
+
+    // Vulnerable AES with ECB and ISO10126Padding
+    fun vulnerableAesEcbIso10126Padding(data: String): String {
+        try {
+            val key = "1234567890123456".toByteArray()
+            val secretKeySpec = SecretKeySpec(key, "AES")
+
+            val cipher = Cipher.getInstance("AES/ECB/ISO10126Padding")
+            cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec)
+
+            val encryptedData = cipher.doFinal(data.toByteArray())
+            return Base64.encodeToString(encryptedData, Base64.DEFAULT)
+        } catch (e: Exception) {
+            return "Encryption error: ${e.message}"
+        }
+    }
+
+    // Vulnerable DES with ECB and PKCS5Padding
+    fun vulnerableDesEcbPkcs5Padding(data: String): String {
+        try {
+            val keySpec = DESKeySpec("12345678".toByteArray())
+            val keyFactory = SecretKeyFactory.getInstance("DES")
+            val secretKey: Key = keyFactory.generateSecret(keySpec)
+
+            val cipher = Cipher.getInstance("DES/ECB/PKCS5Padding")
+            cipher.init(Cipher.ENCRYPT_MODE, secretKey)
+
+            val encryptedData = cipher.doFinal(data.toByteArray())
+            return Base64.encodeToString(encryptedData, Base64.DEFAULT)
+        } catch (e: Exception) {
+            return "Encryption error: ${e.message}"
+        }
+    }
+
+    // Vulnerable 3DES with ECB and PKCS5Padding
+    fun vulnerable3DesEcbPkcs5Padding(data: String): String {
+        try {
+            val keySpec = DESedeKeySpec("123456789012345678901234".toByteArray())
+            val keyFactory = SecretKeyFactory.getInstance("DESede")
+            val secretKey: Key = keyFactory.generateSecret(keySpec)
+
+            val cipher = Cipher.getInstance("DESede/ECB/PKCS5Padding")
+            cipher.init(Cipher.ENCRYPT_MODE, secretKey)
+
+            val encryptedData = cipher.doFinal(data.toByteArray())
+            return Base64.encodeToString(encryptedData, Base64.DEFAULT)
+        } catch (e: Exception) {
+            return "Encryption error: ${e.message}"
+        }
+    }
+
+    // Test and return results
+    fun mastgTest(): String {
+        val sensitiveString = "Hello from OWASP MASTG!"
+
+        val results = listOf(
+            "AES Default: ${vulnerableAesEncryption(sensitiveString)}",
+            "AES ECB NoPadding: ${vulnerableAesEcbNoPadding(sensitiveString)}",
+            "AES ECB PKCS5Padding: ${vulnerableAesEcbPkcs5Padding(sensitiveString)}",
+            "AES ECB ISO10126Padding: ${vulnerableAesEcbIso10126Padding(sensitiveString)}",
+            "DES ECB PKCS5Padding: ${vulnerableDesEcbPkcs5Padding(sensitiveString)}",
+            "3DES ECB PKCS5Padding: ${vulnerable3DesEcbPkcs5Padding(sensitiveString)}"
+        )
+
+        return results.joinToString("\n")
+    }
+}