reverse-skills-max: initial public release (restored, redacted, hardened)

vendor-new/analyst-ai-pack/skills/extracting-encryption-keys-from-binaries/scripts/analyst.py

@@ -0,0 +1,74 @@
+#!/usr/bin/env python3
+"""Surface candidate encryption keys in a binary.
+
+Finds key-sized (16/24/32-byte) high-entropy regions and extracts printable hex/base64 strings
+that match common key lengths. Reports offsets and candidate types. Reads bytes statically;
+executes nothing. Entropy is a heuristic — confirm candidates by attempting decryption.
+"""
+from __future__ import annotations
+
+import argparse
+import json
+import math
+import re
+import sys
+from collections import Counter
+from pathlib import Path
+
+KEY_SIZES = (16, 24, 32)
+ENTROPY_THRESHOLD = 3.7  # bits over a small window; tuned to flag random-looking blocks
+RE_HEXKEY = re.compile(rb"\b[0-9a-fA-F]{32,64}\b")
+RE_B64KEY = re.compile(rb"\b[A-Za-z0-9+/]{24,44}={0,2}\b")
+
+
+def _entropy(chunk: bytes) -> float:
+    if not chunk:
+        return 0.0
+    counts = Counter(chunk)
+    total = len(chunk)
+    return -sum((c / total) * math.log2(c / total) for c in counts.values())
+
+
+def _high_entropy_regions(data: bytes) -> list[dict]:
+    out = []
+    step = 8
+    seen_offsets: set[int] = set()
+    for size in KEY_SIZES:
+        for i in range(0, len(data) - size, step):
+            window = data[i:i + size]
+            # require byte diversity close to the window size (random key material)
+            if len(set(window)) >= size - 2 and _entropy(window) >= ENTROPY_THRESHOLD:
+                if all(abs(i - o) >= size for o in seen_offsets):
+                    out.append({"offset": i, "size": size,
+                                "entropy": round(_entropy(window), 3),
+                                "hex": window.hex()})
+                    seen_offsets.add(i)
+            if len(out) > 200:
+                return out
+    return out
+
+
+def keys(path: str) -> dict:
+    data = Path(path).read_bytes()
+    hex_keys = sorted({m.decode("ascii") for m in RE_HEXKEY.findall(data)})[:50]
+    b64_keys = sorted({m.decode("ascii") for m in RE_B64KEY.findall(data)})[:50]
+    return {
+        "high_entropy_key_candidates": _high_entropy_regions(data)[:50],
+        "hex_string_keys": hex_keys,
+        "base64_string_keys": b64_keys,
+        "note": "confirm any candidate by decrypting known ciphertext; entropy alone is weak",
+    }
+
+
+def main(argv: list[str] | None = None) -> int:
+    parser = argparse.ArgumentParser(description="Extract candidate keys from a binary")
+    sub = parser.add_subparsers(dest="cmd", required=True)
+    p = sub.add_parser("keys")
+    p.add_argument("file")
+    args = parser.parse_args(argv)
+    print(json.dumps(keys(args.file), indent=2))
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())