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8df6aa0 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 | #!/usr/bin/env python3
"""CVSS 3.1 base-score computation + vector builder.
Implements the official FIRST CVSS v3.1 specification formulas so every
benchmark record carries a mathematically consistent vector and score.
Reference: https://www.first.org/cvss/v3.1/specification-document
"""
from __future__ import annotations
AV = {"N": 0.85, "A": 0.62, "L": 0.55, "P": 0.20}
AC = {"L": 0.77, "H": 0.44}
PR_U = {"N": 0.85, "L": 0.62, "H": 0.27} # scope unchanged
PR_C = {"N": 0.85, "L": 0.68, "H": 0.50} # scope changed
UI = {"N": 0.85, "R": 0.62}
CIA = {"H": 0.56, "L": 0.22, "N": 0.0}
def _roundup(value: float) -> float:
"""CVSS roundup: ceil(value * 10) / 10, with a 0-floor."""
int_input = round(value * 100000)
if int_input % 10000 == 0:
return int_input / 100000.0
return (round((int_input / 10000)) + 1) / 10.0
def severity_from_score(score: float) -> str:
if score == 0.0:
return "None"
if score < 4.0:
return "Low"
if score < 7.0:
return "Medium"
if score < 9.0:
return "High"
return "Critical"
def compute_base_vector(
*,
av: str = "N",
ac: str = "L",
pr: str = "N",
ui: str = "N",
s: str = "U",
c: str = "H",
i: str = "H",
a: str = "H",
) -> tuple[str, float]:
"""Return (CVSS:3.1/... vector string, base_score float)."""
av, ac, pr, ui, s, c, i, a = (x.upper() for x in (av, ac, pr, ui, s, c, i, a))
vector = f"CVSS:3.1/AV:{av}/AC:{ac}/PR:{pr}/UI:{ui}/S:{s}/C:{c}/I:{i}/A:{a}"
if s == "C":
pr_val = PR_C[pr]
else:
pr_val = PR_U[pr]
iss = 1 - ((1 - CIA[c]) * (1 - CIA[i]) * (1 - CIA[a]))
if s == "U":
impact = 6.42 * iss
else:
impact = 7.52 * (iss - 0.029) - 3.25 * (iss * 0.9731 - 0.02) ** 13
exploitability = 8.22 * AV[av] * AC[ac] * pr_val * UI[ui]
if impact <= 0:
score = 0.0
elif s == "U":
score = _roundup(min(impact + exploitability, 10.0))
else:
score = _roundup(min(1.08 * (impact + exploitability), 10.0))
return vector, round(score, 1)
def cvss_for(vuln_key: str, difficulty: str) -> tuple[str, float]:
"""Hand-tuned default CVSS vectors per vulnerability archetype.
'difficulty' nudges PR/UI slightly: enterprise examples tend to require
a foothold or user interaction, so the score is realistic not maximal.
Returns (vector, score).
"""
enterprise = difficulty in ("Real-world enterprise", "Expert")
base = _DEFAULT_VECTORS.get(vuln_key, _DEFAULT_VECTORS["__default__"])
av, ac, pr, ui, s, c, i, a = [base[f"AV"], base["AC"], base["PR"], base["UI"],
base["S"], base["C"], base["I"], base["A"]]
# Real-world enterprise scenarios often require low-priv/UI foothold.
if enterprise and pr == "N":
pr = "L"
if enterprise and ui == "N":
ui = "R"
return compute_base_vector(av=av, ac=ac, pr=pr, ui=ui, s=s, c=c, i=i, a=a)
# Default vectors keyed by vulnerability_name (normalized lower). Each maps to
# the dominant realistic exploitability/impact profile for that weakness.
_DEFAULT_VECTORS = {
"__default__": {"AV": "N", "AC": "L", "PR": "N", "UI": "N", "S": "U", "C": "H", "I": "H", "A": "H"},
"sql injection": {"AV": "N", "AC": "L", "PR": "N", "UI": "N", "S": "U", "C": "H", "I": "H", "A": "H"},
"cross-site scripting": {"AV": "N", "AC": "L", "PR": "N", "UI": "R", "S": "C", "C": "L", "I": "L", "A": "N"},
"ssrf": {"AV": "N", "AC": "L", "PR": "N", "UI": "N", "S": "C", "C": "H", "I": "L", "A": "L"},
"command injection": {"AV": "N", "AC": "L", "PR": "N", "UI": "N", "S": "U", "C": "H", "I": "H", "A": "H"},
"path traversal": {"AV": "N", "AC": "L", "PR": "N", "UI": "N", "S": "U", "C": "H", "I": "N", "A": "N"},
"xml external entity": {"AV": "N", "AC": "L", "PR": "N", "UI": "R", "S": "U", "C": "H", "I": "L", "A": "L"},
"insecure direct object reference": {"AV": "N", "AC": "L", "PR": "L", "UI": "N", "S": "U", "C": "H", "I": "H", "A": "N"},
"broken access control": {"AV": "N", "AC": "L", "PR": "L", "UI": "N", "S": "U", "C": "H", "I": "H", "A": "N"},
"broken authentication": {"AV": "N", "AC": "L", "PR": "N", "UI": "N", "S": "U", "C": "H", "I": "H", "A": "N"},
"broken authorization": {"AV": "N", "AC": "L", "PR": "L", "UI": "N", "S": "U", "C": "H", "I": "H", "A": "N"},
"jwt vulnerabilities": {"AV": "N", "AC": "H", "PR": "N", "UI": "N", "S": "U", "C": "H", "I": "H", "A": "N"},
"oauth vulnerabilities": {"AV": "N", "AC": "H", "PR": "N", "UI": "R", "S": "U", "C": "H", "I": "H", "A": "N"},
"session management": {"AV": "N", "AC": "L", "PR": "N", "UI": "R", "S": "U", "C": "H", "I": "H", "A": "N"},
"cross-site request forgery": {"AV": "N", "AC": "L", "PR": "N", "UI": "R", "S": "U", "C": "H", "I": "H", "A": "N"},
"insecure file upload": {"AV": "N", "AC": "L", "PR": "N", "UI": "N", "S": "U", "C": "H", "I": "H", "A": "H"},
"insecure deserialization": {"AV": "N", "AC": "L", "PR": "N", "UI": "N", "S": "U", "C": "H", "I": "H", "A": "H"},
"open redirect": {"AV": "N", "AC": "L", "PR": "N", "UI": "R", "S": "C", "C": "L", "I": "L", "A": "N"},
"race condition": {"AV": "N", "AC": "H", "PR": "L", "UI": "N", "S": "U", "C": "L", "I": "H", "A": "L"},
"insecure cryptography": {"AV": "N", "AC": "H", "PR": "N", "UI": "N", "S": "U", "C": "H", "I": "N", "A": "N"},
"hardcoded secrets": {"AV": "N", "AC": "L", "PR": "L", "UI": "N", "S": "U", "C": "H", "I": "N", "A": "N"},
"business logic": {"AV": "N", "AC": "L", "PR": "L", "UI": "R", "S": "U", "C": "H", "I": "H", "A": "N"},
"missing rate limiting": {"AV": "N", "AC": "L", "PR": "N", "UI": "N", "S": "U", "C": "N", "I": "L", "A": "H"},
"sensitive data logging": {"AV": "L", "AC": "L", "PR": "L", "UI": "N", "S": "U", "C": "H", "I": "N", "A": "N"},
"header injection": {"AV": "N", "AC": "L", "PR": "N", "UI": "R", "S": "C", "C": "L", "I": "L", "A": "N"},
"prompt injection": {"AV": "N", "AC": "L", "PR": "N", "UI": "R", "S": "C", "C": "H", "I": "H", "A": "L"},
"rag security": {"AV": "N", "AC": "L", "PR": "N", "UI": "R", "S": "C", "C": "H", "I": "L", "A": "L"},
"mcp security": {"AV": "N", "AC": "L", "PR": "N", "UI": "R", "S": "C", "C": "H", "I": "H", "A": "L"},
"ai agent security": {"AV": "N", "AC": "L", "PR": "N", "UI": "R", "S": "C", "C": "H", "I": "H", "A": "H"},
"graphql security": {"AV": "N", "AC": "L", "PR": "L", "UI": "N", "S": "U", "C": "H", "I": "H", "A": "N"},
"rest api security": {"AV": "N", "AC": "L", "PR": "L", "UI": "N", "S": "U", "C": "H", "I": "H", "A": "N"},
"grpc security": {"AV": "N", "AC": "L", "PR": "L", "UI": "N", "S": "U", "C": "H", "I": "H", "A": "N"},
"cloud misconfiguration": {"AV": "N", "AC": "L", "PR": "L", "UI": "N", "S": "C", "C": "H", "I": "H", "A": "H"},
"kubernetes security": {"AV": "N", "AC": "L", "PR": "L", "UI": "N", "S": "C", "C": "H", "I": "H", "A": "H"},
"docker security": {"AV": "L", "AC": "L", "PR": "L", "UI": "N", "S": "C", "C": "H", "I": "H", "A": "H"},
}
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