cvss/v31vector.go: fix temporal score, add temporal score tests

2 files changed, 127 insertions, 6 deletions

diff --git a/cvss/v31vector.go b/cvss/v31vector.go
index a9d5205..b191ce0 100644
--- a/cvss/v31vector.go
+++ b/cvss/v31vector.go
@@ -119,6 +119,18 @@ func isV31VectorString(s string) bool {
          v31VecRe.MatchString(s)
 }
 
+// Does the map have at least one of the keys needed for a temporal
+// score defined?
+func hasTemporalScoreKeys(keys map[Key]v3Metric) bool {
+  ecm, ecm_ok := keys[v3ExploitCodeMaturity] // E
+  rl, rl_ok := keys[v3RemediationLevel] // RL
+  rc, rc_ok := keys[v3ReportConfidence] // RC
+
+  return (ecm_ok && ecm != v3ENotDefined) ||
+         (rl_ok && rl != v3RLNotDefined) ||
+         (rc_ok && rc != v3RCNotDefined)
+}
+
 // roundup implemention (from CVSS v3.1 spec, appendix A)
 func roundup(val float64) float64 {
   return math.Ceil(10.0 * val) / 10.0
@@ -343,8 +355,18 @@ func (v v31Vector) Scores() (Scores, error) {
     // calculate impact
     impact := 0.0
     if scopeChanged {
-      // impact = 7.52 * (iss - 0.029) - 3.25 * math.Pow(iss - 0.02, 15)
-      impact = 6.42 * iss
+      impact = 7.52 * (iss - 0.029) - 3.25 * math.Pow(iss - 0.02, 15)
+
+      // adjust privileges required based on scopeChanged
+      // (CVSS v3.1 spec, section 7.4, table 16)
+      if pr, ok := keys[v3PrivilegesRequired]; ok {
+        switch pr {
+        case v3PRLow: // PR:L
+          privsRequired = 0.68
+        case v3PRHigh: // PR:H
+          privsRequired = 0.50
+        }
+      }
     } else {
       impact = 6.42 * iss
     }
@@ -362,7 +384,10 @@ func (v v31Vector) Scores() (Scores, error) {
   }
 
   // temporal score (CVSS v3.1 spec, section 7.2)
-  tempScore := roundup(baseScore * ecm * remediationLevel * reportConfidence)
+  tempScore := 0.0
+  if hasTemporalScoreKeys(keys) {
+    tempScore = roundup(baseScore * ecm * remediationLevel * reportConfidence)
+  }
 
   // environmental score (CVSS v3.1 spec, section 7.3)
   //
diff --git a/cvss/v31vector_test.go b/cvss/v31vector_test.go
index 86fb8eb..519b18a 100644
--- a/cvss/v31vector_test.go
+++ b/cvss/v31vector_test.go
@@ -573,15 +573,111 @@ func TestV31VectorScores(t *testing.T) {
   }, {
     name: "initial I:H",
     val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
-    exp: []float64 { 9.8, 9.8, 0.0 },
+    exp: []float64 { 9.8, 0.0, 0.0 },
   }, {
     name: "initial A:L",
     val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
-    exp: []float64 { 5.3, 5.3, 0.0 },
+    exp: []float64 { 5.3, 0.0, 0.0 },
   }, {
     name: "AV:A",
     val: "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
-    exp: []float64 { 6.3, 6.3, 0.0 },
+    exp: []float64 { 6.3, 0.0, 0.0 },
+  }, {
+    name: "AV:L",
+    val: "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
+    exp: []float64 { 5.9, 0.0, 0.0 },
+  }, {
+    name: "AV:P",
+    val: "CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
+    exp: []float64 { 4.3, 0.0, 0.0 },
+  }, {
+    name: "AC:H",
+    val: "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L",
+    exp: []float64 { 5.6, 0.0, 0.0 },
+  }, {
+    name: "PR:L",
+    val: "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L",
+    exp: []float64 { 6.3, 0.0, 0.0 },
+  }, {
+    name: "PR:H",
+    val: "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L",
+    exp: []float64 { 4.7, 0.0, 0.0 },
+  }, {
+    name: "UI:R",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L",
+    exp: []float64 { 6.3, 0.0, 0.0 },
+  }, {
+    name: "S:C",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L",
+    exp: []float64 { 8.3, 0.0, 0.0 },
+  }, {
+    name: "C:N",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L",
+    exp: []float64 { 6.5, 0.0, 0.0 },
+  }, {
+    name: "C:H",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L",
+    exp: []float64 { 8.6, 0.0, 0.0 },
+  }, {
+    name: "I:N",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L",
+    exp: []float64 { 6.5, 0.0, 0.0 },
+  }, {
+    name: "I:H",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L",
+    exp: []float64 { 8.6, 0.0, 0.0 },
+  }, {
+    name: "A:N",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
+    exp: []float64 { 6.5, 0.0, 0.0 },
+  }, {
+    name: "A:H",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
+    exp: []float64 { 8.6, 0.0, 0.0 },
+  }, {
+    name: "E:U",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:U",
+    exp: []float64 { 7.3, 6.7, 0.0 },
+  }, {
+    name: "E:P",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P",
+    exp: []float64 { 7.3, 6.9, 0.0 },
+  }, {
+    name: "E:F",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:F",
+    exp: []float64 { 7.3, 7.1, 0.0 },
+  }, {
+    name: "E:H",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:H",
+    exp: []float64 { 7.3, 7.3, 0.0 },
+  }, {
+    name: "RL:O",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/RL:O",
+    exp: []float64 { 7.3, 7.0, 0.0 },
+  }, {
+    name: "RL:T",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/RL:T",
+    exp: []float64 { 7.3, 7.1, 0.0 },
+  }, {
+    name: "RL:W",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/RL:W",
+    exp: []float64 { 7.3, 7.1, 0.0 },
+  }, {
+    name: "RL:U",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/RL:U",
+    exp: []float64 { 7.3, 7.3, 0.0 },
+  }, {
+    name: "RC:U",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/RC:U",
+    exp: []float64 { 7.3, 6.8, 0.0 },
+  }, {
+    name: "RC:R",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/RC:R",
+    exp: []float64 { 7.3, 7.1, 0.0 },
+  }, {
+    name: "RC:C",
+    val: "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/RC:C",
+    exp: []float64 { 7.3, 7.3, 0.0 },
   }}
 
   for _, test := range(tests) {