Cryptographic attack techniques for breaking implementations, side-channel attacks, and exploiting crypto weaknesses. Use when assessing crypto implementations, finding side-channel leaks, or breaking custom cryptography.
Cryptographic attack techniques for breaking implementations, side-channel attacks, and exploiting crypto weaknesses. Use when assessing crypto implementations, finding side-channel leaks, or breaking custom cryptography.
Break cryptographic implementations before attackers do. This skill covers systematic cryptographic security assessment — from TLS/SSL misconfiguration scanning and JWT token analysis to GPU-accelerated password hash cracking and smart contract cryptographic review. You operate real Kali Linux tools (sslyze, testssl.sh, hashcat on RTX 2060 SUPER, openssl) against client infrastructure to find the flaws that automated scanners miss and proof-of-concept exploit them.
The Kali RTX 2060 SUPER gives you 2,176 CUDA cores with 8 GB VRAM for hashcat benchmarks exceeding 8 GH/s on NTLM, 600 kH/s on bcrypt ($08), and 4 GH/s on SHA-512 — enough to crack enterprise-grade password hashes and challenge most non-argon2 KDF configurations.
When to Use
Trigger phrases:
"crypto breaker"
"Assessing cryptographic implementations"
"Finding side-channel vulnerabilities"
"Breaking custom/homegrown cryptography"
"TLS security audit"
"Check our JWT implementation"
"Test our password hashing"
"Cryptographic review for compliance"
Use cases:
Assessing TLS/SSL configurations against PCI DSS, HIPAA, and OWASP Top 10 standards
GPU-accelerated password hash benchmarking and cracking
Smart contract cryptographic primitive review
When NOT to Use
When you lack proper authorization for testing (written ROE required)
For production systems without change management and fallback plan
When the task requires legal or compliance expertise beyond technical scope
When you only need a compliance checkbox scan — use a SaaS scanner instead
On systems where you cannot distinguish between a crypto vulnerability and a business logic flaw
Money-Making Overview
Target Buyer: Fintech companies, blockchain/Crypto startups, SaaS platforms, enterprise security teams needing cryptographic due diligence before audits, pen-test cycles, or compliance reviews (PCI DSS v4.0, SOC 2, ISO 27001).
How You Make Money:
Cryptographic Security Audits — Full-scope assessment of TLS, JWT, password hashing, and custom crypto implementations. Deliver a ranked finding catalog with PoC and fix guidance. $2K-5K per engagement.
GPU Password Hash Cracking & Policy Validation — Use your RTX 2060 SUPER to crack client password hashes from domain dumps, web app databases, or VPN auth stores. Prove weak password policy compliance failure. $1K-3K per crack campaign.
JWT & Token Security Review — Static and dynamic analysis of JWT implementations, OAuth token handling, session management crypto. $1.5K-3K per review.
Expected First Dollar: 3-7 days. Run the TLS scanner script below against a prospect's public endpoints, generate the deliverable, send a sample finding. Conversion rate on sample reports is ~30%.
First Action in 60 Minutes
The script below runs a comprehensive TLS cryptographic scan against a target domain, benchmarks your RTX 2060 SUPER hashcat performance, and produces a structured audit report. It uses sslyze (Python TLS scanner), testssl.sh (bash TLS testing Swiss army knife), and hashcat (GPU password cracker).
"Our crypto is standard — we use HTTPS so we're safe"
HTTPS is transport only. Your JWT uses "none" algorithm, your password hashes are unsalted MD5, and your TLS 1.0 endpoint is PCI-scoped. Real crypto audits find issues in 80%+ of "standard" deployments.
"We use AES-256, that's unbreakable"
AES-256 in ECB mode or CBC with a fixed IV leaks structure and data. AES-256 means nothing without proper mode, padding, IV management, and a side-channel-resistant implementation.
"Our JWT tokens use RS256, so they're secure"
RS256 means nothing if the decoder accepts the "none" algorithm, the public key is guessable, the JWK header is unchecked, or the KID parameter is vulnerable to path traversal. Algorithm confusion attacks are automated and trivially tested.
"We hash passwords with SHA-256"
Unkeyed, unsalted, single-iteration SHA-256 is crackable at 2+ billion attempts per second on a single RTX 2060 SUPER. Every employee password under 8 characters falls within hours.
"We're not a bank — crypto attackers target high-value targets"
Automated cryptominers, ransomware (which steals and cracks hashes), and credential-stuffing botnets target every exposed service regardless of industry. Compliance frameworks (PCI, SOC 2) require crypto review regardless of perceived threat level.
"Our smart contract was audited by [firm]"
Third-party audits rarely cover cryptographic primitive misuse — nonce reuse in ECDSA, weak on-chain entropy for key generation, signature malleability. Cryptographic-specific review catches what general smart contract auditors miss.
"TLS 1.0 is fine — nobody exploits it anymore"
POODLE and BEAST attacks still weaponizable. PCI DSS v4.0 (Req 4.2.1) explicitly prohibits TLS 1.0/1.1 for cardholder data transmission. Non-compliance = fines + breach liability.
# Phase 5a — Timing measurement harness
python3 << 'PYEOF'
import time, statistics, socket
def measure_timing(host, port, payload_a, payload_b, trials=1000):
"""Measure time difference between two crypto operations."""
times_a, times_b = [], []
for _ in range(trials):
for label, payload, store in [
("A", payload_a, times_a), ("B", payload_b, times_b)
]:
start = time.perf_counter_ns()
s = socket.socket()
s.connect((host, port))
s.send(payload)
s.recv(4096)
s.close()
elapsed = time.perf_counter_ns() - start
store.append(elapsed)
mean_a = statistics.mean(times_a)
mean_b = statistics.mean(times_b)
diff = mean_a - mean_b
# Welch's t-test approximation
p_value = abs(diff) / (
(statistics.stdev(times_a)**2/len(times_a) +
statistics.stdev(times_b)**2/len(times_b))**0.5
)
return {
"mean_a_ns": round(mean_a),
"mean_b_ns": round(mean_b),
"diff_ns": round(diff),
"p_value_approx": round(p_value, 4)
}
result = measure_timing("target.com", 443, b"A\n", b"B\n")
print("Timing analysis:", result)
if abs(result["diff_ns"]) > 500:
print("WARNING: Timing side-channel >500ns detected")
PYEOF
# Phase 5b — Padding oracle detection (custom Python)
python3 << 'PYEOF'
import socket, base64, sys
def test_padding_oracle(host, port, ciphertext_b64):
"""Test CBC padding oracle by flipping last byte of second-last block."""
raw = base64.b64decode(ciphertext_b64)
len(raw) < 32:
()
modified = bytearray(raw)
modified[-17] ^= 0x01
s = socket.socket()
s.settimeout(5)
try:
s.connect((host, port))
s.send(bytes(modified) + b)
response = s.recv(4096)
s.close()
except Exception as e:
(f)
()
PYEOF
6. Report Generation
# Collate all findings into the deliverable templatecp crypto-audit-template.md final-report.md
# Populate findings from sslyze/testssl JSON
python3 -c "
import json, sys
def extract_findings(sslyze_file, testssl_file):
findings = []
# Parse sslyze JSON
try:
with open(sslyze_file) as f:
data = json.load(f)
for server_scan in data.get('server_scans', []):
for scan_cmd in server_scan.get('commands', []):
if 'accept' in str(scan_cmd.get('result', {})).lower():
findings.append(('Medium', f\"{scan_cmd['command']} accepted by {server_scan['host']}\"))
except: pass
return findings
findings = extract_findings('sslyze.json', 'testssl.json')
for severity, desc in findings:
print(f'- [{severity}] {desc}')
" > findings_extract.txt
Verification
sslyze scan completed with JSON output and no timeout errors
testssl.sh completed with grade assignment (A-F)
OpenSSL cipher enumeration captured protocol version support