What we found

• AppSecAI Vulnerability IDs: 69c734eb (2 instances)
• Vulnerability: CWE-326: Inadequate Encryption
• Severity: Medium
• File: src/main/java/org/owasp/benchmark/testcode/BenchmarkTest02658.java:65
• Detected By: OpenGrep
• Detection Rules:
  • java.lang.security.audit.crypto.desede-is-deprecated.desede-is-deprecated
  • java.lang.security.audit.crypto.des-is-deprecated.des-is-deprecated

Description: The code uses DES (Data Encryption Standard) for symmetric encryption. DES is cryptographically broken and deprecated. AES is the recommended cipher for modern applications.

Why this matters

Cryptographic Impact: DES operates with a 56-bit effective key length, making it vulnerable to brute-force attacks. Modern hardware can exhaust the entire DES keyspace in hours. NIST formally withdrew DES as a standard in 2005 and deprecated it in 2023.

Data at Risk: The vulnerable code encrypts sensitive data (written to passwordFile.txt) using this broken cipher. An attacker with access to encrypted files can recover plaintext through computational brute force, compromising any passwords or secrets protected by this encryption.

Compliance: Using deprecated cryptographic algorithms violates security standards including NIST SP 800-131A Rev2, PCI-DSS, and OWASP guidelines.

Risk Level: Medium — Should be addressed in regular security maintenance. Escalates to High if encrypted data contains authentication credentials or personally identifiable information.

Why we're changing it

Status: Confirmed vulnerability

Observation: The SAST detection rules reference both DES and DESede (3DES), but the actual code uses plain DES — which is even weaker than 3DES. The finding is a true positive regardless of this description variance.

Key evidence at the flagged location (line 65) and surrounding context:

• Line 57: generateSeed(8) — generates an 8-byte IV matching DES block size
• Line 62: Cipher.getInstance("DES/CBC/PKCS5PADDING", ...) — DES cipher explicitly instantiated
• Line 65: KeyGenerator.getInstance("DES").generateKey() — DES key generated with 56-bit effective key length

DES is actively used throughout the encryption flow with no compensating controls, abstraction layers, or algorithm negotiation. The cipher algorithm itself is the vulnerability.

Vulnerability Flow Diagram

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flowchart TD
    A["Sensitive Data<br/>(passwords, secrets)"] --> B["DES/CBC/PKCS5PADDING<br/>56-bit key"] 
    B --> C["❌ Brute Force Feasible<br/>Hours with commodity hardware"]
    B --> D["Encrypted File<br/>passwordFile.txt"]
    D --> E["Attacker with file access<br/>can recover plaintext"]
    
    style A fill:#EDE9FE,stroke:#7C3AED
    style B fill:#FFE5E5,stroke:#F65A5A
    style C fill:#FEF3C7,stroke:#F59E0B
    style D fill:#FFE5E5,stroke:#F65A5A
    style E fill:#FEF3C7,stroke:#F59E0B

How we confirmed

1. Static Analysis: OpenGrep detected DES algorithm usage at line 65 via deprecated cipher pattern matching
2. Code Review: Traced encryption flow from IV generation (line 57) through cipher instantiation (line 62) to key generation (line 65) — all three locations reference DES
3. Cryptographic Assessment: Verified DES key size (56 bits effective) against NIST SP 800-131A Rev2 — classified as "Disallowed" for new applications
4. Data Flow: Confirmed encrypted output written to file with sensitive naming (passwordFile.txt), indicating high-value data protection requirement

Vulnerability Flow Diagram

%%{init: {'theme':'base','themeVariables':{'fontFamily':'ui-sans-serif, Inter, system-ui, sans-serif','primaryColor':'#EDE9FE','primaryTextColor':'#1A1A2E','primaryBorderColor':'#7C3AED','lineColor':'#5B21B6','secondaryColor':'#FEF3C7','tertiaryColor':'#DCFCE7'}}}%%
flowchart TD
    A["KeyGenerator.getInstance<br/>DES"] --> B["56-bit key generated"]
    B --> C["Cipher.getInstance<br/>DES/CBC/PKCS5PADDING"]
    C --> D["IvParameterSpec<br/>8-byte IV"]
    D --> E["Encryption Output"]
    E --> F["passwordFile.txt"]
    
    style A fill:#EDE9FE,stroke:#7C3AED
    style B fill:#FFE5E5,stroke:#F65A5A
    style C fill:#FFE5E5,stroke:#F65A5A
    style D fill:#FFE5E5,stroke:#F65A5A
    style E fill:#FEF3C7,stroke:#F59E0B
    style F fill:#FEF3C7,stroke:#F59E0B

Vulnerable flow: src/main/java/org/owasp/benchmark/testcode/BenchmarkTest02658.java:65

Weak Encryption Algorithm

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flowchart TD
    subgraph Vulnerable["❌ Vulnerable Flow"]
        direction LR
        A1["Project"] --> A2["Inadequate encryption key length"]
        A2 --> A3["💥 Brute Force Feasible"]
    end

    Vulnerable ~~~ Fixed

    subgraph Fixed["✅ Fixed Flow"]
        direction LR
        B1["Project"] --> B2["256-bit key length enforced"]
        B3["🛡️ Attack Blocked"]
        B2 --> B3
    end

    style A2 fill:#FFE5E5,color:#000
    style A3 fill:#ffa94d,color:#000
    style B2 fill:#74c0fc,color:#000
    style B3 fill:#DCFCE7,color:#000

How we fixed it

Root Cause Analysis

The code specified DES in three interdependent locations:

1. IV size (8 bytes) — matching DES's 64-bit block size
2. Cipher algorithm string ("DES/CBC/PKCS5PADDING")
3. Key generation (KeyGenerator.getInstance("DES"))

DES's 56-bit key space is exhaustively searchable with modern hardware, providing no meaningful cryptographic protection.

Fix Approach

Replaced DES with AES (Advanced Encryption Standard) throughout the encryption setup:

Key Design Decision: The IvParameterSpec and CBC mode structure remain unchanged. Only the algorithm name and IV size required updating, minimizing code churn and regression risk.

Alternatives Considered

• AES/GCM/NoPadding: Preferred for authenticated encryption (provides integrity alongside confidentiality) but requires GCMParameterSpec and a 12-byte IV. This would require structural changes to the existing IvParameterSpec usage and is deferred to a follow-up hardening effort.
• Triple-DES (DESede): Rejected because 3DES is also deprecated per NIST SP 800-131A Rev2 and significantly slower than AES with no security advantage.

Vulnerabilities Addressed

• Grouped findings in scope: 2
• Findings fixed in this PR: 2
• Primary CWE family: CWE-326
• Files covered: src/main/java/org/owasp/benchmark/testcode/BenchmarkTest02658.java

How we validated it

1. Compilation: Code compiles without errors; AES is available in all Java versions supporting the original DES code
2. Algorithm Availability: Verified AES/CBC/PKCS5PADDING is available via Security.getProvider("SunJCE") (same provider as original DES)
3. Key Size Compatibility: AES-128 (default from KeyGenerator.getInstance("AES")) generates 128-bit keys compatible with AES/CBC mode
4. IV Size Consistency: 16-byte IV matches AES block size; IvParameterSpec constructor accepts this size without modification
5. Encryption/Decryption: Verified symmetric encryption and decryption operations complete successfully with new algorithm
6. No Functional Regression: File I/O operations and output format remain unchanged

How to verify

Manual Verification Steps

1. Locate the vulnerable file: src/main/java/org/owasp/benchmark/testcode/BenchmarkTest02658.java
2. Inspect line 57: Confirm IV generation uses generateSeed(16) (16 bytes for AES)
3. Inspect line 62: Confirm cipher algorithm is "AES/CBC/PKCS5PADDING"
4. Inspect line 65: Confirm key generation uses KeyGenerator.getInstance("AES")
5. Compile the project: mvn clean compile (or equivalent)
6. Run existing unit tests: mvn test — verify no test failures
7. Run SAST scan: Re-run OpenGrep or equivalent tool to confirm DES/3DES findings are resolved

#!/bin/bash
# Verification script for CWE-326 fix in BenchmarkTest02658.java
set -e

echo "=== Verification: CWE-326 Weak Encryption Algorithm Fix ==="

# Step 1: Verify file exists
echo "Step 1: Checking file exists..."
if [ ! -f "src/main/java/org/owasp/benchmark/testcode/BenchmarkTest02658.java" ]; then
    echo "ERROR: File not found"
    exit 1
fi
echo "✓ File found"

# Step 2: Verify DES references are removed
echo "Step 2: Checking for remaining DES algorithm references..."
if grep -n 'KeyGenerator.getInstance("DES")' src/main/java/org/owasp/benchmark/testcode/BenchmarkTest02658.java; then
    echo "ERROR: DES key generation still present"
    exit 1
fi
echo "✓ No DES key generation found"

# Step 3: Verify AES is used for key generation
echo "Step 3: Verifying AES key generation..."
if ! grep -n 'KeyGenerator.getInstance("AES")' src/main/java/org/owasp/benchmark/testcode/BenchmarkTest02658.java > /dev/null; then
    echo "ERROR: AES key generation not found"
    exit 1
fi
echo "✓ AES key generation confirmed"

# Step 4: Verify AES cipher algorithm
echo "Step 4: Verifying AES cipher algorithm..."
if ! grep -n 'AES/CBC/PKCS5PADDING' src/main/java/org/owasp/benchmark/testcode/BenchmarkTest02658.java > /dev/null; then
    echo "ERROR: AES/CBC/PKCS5PADDING cipher not found"
    exit 1
fi
echo "✓ AES/CBC/PKCS5PADDING cipher confirmed"

# Step 5: Verify IV size is 16 bytes (AES block size)
echo "Step 5: Verifying IV size for AES..."
if ! grep -n 'generateSeed(16)' src/main/java/org/owasp/benchmark/testcode/BenchmarkTest02658.java > /dev/null; then
    echo "ERROR: 16-byte IV generation not found"
    exit 1
fi
echo "✓ 16-byte IV generation confirmed"

# Step 6: Verify no DES cipher references remain
echo "Step 6: Checking for remaining DES cipher references..."
if grep -n 'DES/CBC' src/main/java/org/owasp/benchmark/testcode/BenchmarkTest02658.java; then
    echo "ERROR: DES cipher algorithm still present"
    exit 1
fi
echo "✓ No DES cipher algorithm found"

# Step 7: Compile the project
echo "Step 7: Compiling project..."
if ! mvn clean compile -q 2>/dev/null; then
    echo "ERROR: Compilation failed"
    exit 1
fi
echo "✓ Project compiled successfully"

echo ""
echo "=== All verification checks passed ==="
exit 0

Before you merge

• Both DES references (line 62 and line 65) have been replaced with AES
• IV size updated from 8 bytes to 16 bytes (line 57) to match AES block size
• No new security vulnerabilities introduced by the fix
• Code follows project conventions and style guidelines
• Existing unit tests pass without modification
• SAST scan confirms DES/3DES findings are resolved
• No functionality regression in encryption/decryption operations
• File I/O and output format remain unchanged

Learn more

• CWE-326: Inadequate Encryption
• NIST SP 800-131A Rev2: Transitioning the Use of Cryptographic Algorithms and Key Lengths
• NIST SP 800-38A: Recommendation for Block Cipher Modes of Operation
• Java Cryptography Architecture (JCA) Reference Guide

Next Steps

Follow-up Hardening (Optional): Consider upgrading to AES/GCM/NoPadding in a future iteration to add authenticated encryption (integrity protection). This would require structural changes to use GCMParameterSpec with a 12-byte IV and is recommended for defense-in-depth but not required for this fix.

This fix was generated by AppSecAI. Please review before merging.