ext: Parse NVD JSON feed instead of XML

The JSON feed provides some values that are not available in the XML
feed such as CVSSv3.

ext/vulnmdsrc/nvd/json.go

@@ -22,27 +22,39 @@ import (
 )
 
 type nvd struct {
-	Entries []nvdEntry `xml:"entry"`
+	Entries []nvdEntry `json:"CVE_Items"`
 }
 
 type nvdEntry struct {
-	Name              string  `xml:"http://scap.nist.gov/schema/vulnerability/0.4 cve-id"`
-	CVSS              nvdCVSS `xml:"http://scap.nist.gov/schema/vulnerability/0.4 cvss"`
-	PublishedDateTime string  `xml:"http://scap.nist.gov/schema/vulnerability/0.4 published-datetime"`
+	CVE               nvdCVE    `json:"cve"`
+	Impact            nvdImpact `json:"impact"`
+	PublishedDateTime string    `json:"publishedDate"`
 }
 
-type nvdCVSS struct {
-	BaseMetrics nvdCVSSBaseMetrics `xml:"http://scap.nist.gov/schema/cvss-v2/0.2 base_metrics"`
+type nvdCVE struct {
+	Metadata nvdCVEMetadata `json:"CVE_data_meta"`
 }
 
-type nvdCVSSBaseMetrics struct {
-	Score            float64 `xml:"score"`
-	AccessVector     string  `xml:"access-vector"`
-	AccessComplexity string  `xml:"access-complexity"`
-	Authentication   string  `xml:"authentication"`
-	ConfImpact       string  `xml:"confidentiality-impact"`
-	IntegImpact      string  `xml:"integrity-impact"`
-	AvailImpact      string  `xml:"availability-impact"`
+type nvdCVEMetadata struct {
+	CVEID string `json:"ID"`
+}
+
+type nvdImpact struct {
+	BaseMetricV2 nvdBaseMetricV2 `json:"baseMetricV2"`
+}
+
+type nvdBaseMetricV2 struct {
+	CVSSv2 nvdCVSSv2 `json:"cvssV2"`
+}
+
+type nvdCVSSv2 struct {
+	Score            float64 `json:"baseScore"`
+	AccessVector     string  `json:"accessVector"`
+	AccessComplexity string  `json:"accessComplexity"`
+	Authentication   string  `json:"authentication"`
+	ConfImpact       string  `json:"confidentialityImpact"`
+	IntegImpact      string  `json:"integrityImpact"`
+	AvailImpact      string  `json:"availabilityImpact"`
 }
 
 var vectorValuesToLetters map[string]string
@@ -56,8 +68,8 @@ func init() {
 	vectorValuesToLetters["MEDIUM"] = "M"
 	vectorValuesToLetters["LOW"] = "L"
 	vectorValuesToLetters["NONE"] = "N"
-	vectorValuesToLetters["SINGLE_INSTANCE"] = "S"
-	vectorValuesToLetters["MULTIPLE_INSTANCES"] = "M"
+	vectorValuesToLetters["SINGLE"] = "S"
+	vectorValuesToLetters["MULTIPLE"] = "M"
 	vectorValuesToLetters["PARTIAL"] = "P"
 	vectorValuesToLetters["COMPLETE"] = "C"
 }
@@ -66,18 +78,23 @@ func (n nvdEntry) Metadata() *NVDMetadata {
 	metadata := &NVDMetadata{
 		CVSSv2: NVDmetadataCVSSv2{
 			PublishedDateTime: n.PublishedDateTime,
-			Vectors:           n.CVSS.BaseMetrics.String(),
-			Score:             n.CVSS.BaseMetrics.Score,
+			Vectors:           n.Impact.BaseMetricV2.CVSSv2.String(),
+			Score:             n.Impact.BaseMetricV2.CVSSv2.Score,
 		},
 	}
 
 	if metadata.CVSSv2.Vectors == "" {
 		return nil
 	}
+
 	return metadata
 }
 
-func (n nvdCVSSBaseMetrics) String() string {
+func (n nvdEntry) Name() string {
+	return n.CVE.Metadata.CVEID
+}
+
+func (n nvdCVSSv2) String() string {
 	var str string
 	addVec(&str, "AV", n.AccessVector)
 	addVec(&str, "AC", n.AccessComplexity)
@@ -94,7 +111,7 @@ func addVec(str *string, vec, val string) {
 		if let, ok := vectorValuesToLetters[val]; ok {
 			*str = fmt.Sprintf("%s%s:%s/", *str, vec, let)
 		} else {
-			log.WithFields(log.Fields{"value": val, "vector": vec}).Warning("unknown value for CVSSv2 vector")
+			log.WithFields(log.Fields{"value": val, "vector": vec}).Warning("unknown value for CVSS vector")
 		}
 	}
 }

ext/vulnmdsrc/nvd/nvd.go

@@ -19,7 +19,7 @@ package nvd
 import (
 	"bufio"
 	"compress/gzip"
-	"encoding/xml"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
@@ -39,8 +39,8 @@ import (
 )
 
 const (
-	dataFeedURL     string = "https://nvd.nist.gov/feeds/xml/cve/2.0/nvdcve-2.0-%s.xml.gz"
-	dataFeedMetaURL string = "https://nvd.nist.gov/feeds/xml/cve/2.0/nvdcve-2.0-%s.meta"
+	dataFeedURL     string = "https://nvd.nist.gov/feeds/json/cve/1.0/nvdcve-1.0-%s.json.gz"
+	dataFeedMetaURL string = "https://nvd.nist.gov/feeds/json/cve/1.0/nvdcve-1.0-%s.meta"
 
 	appenderName string = "NVD"
 
@@ -96,8 +96,9 @@ func (a *appender) BuildCache(datastore database.Datastore) error {
 			return commonerr.ErrCouldNotParse
 		}
 		var nvd nvd
+
 		r := bufio.NewReader(f)
-		if err = xml.NewDecoder(r).Decode(&nvd); err != nil {
+		if err := json.NewDecoder(r).Decode(&nvd); err != nil {
 			f.Close()
 			log.WithError(err).WithField(logDataFeedName, dataFeedName).Error("could not decode NVD data feed")
 			return commonerr.ErrCouldNotParse
@@ -107,7 +108,7 @@ func (a *appender) BuildCache(datastore database.Datastore) error {
 		for _, nvdEntry := range nvd.Entries {
 			// Create metadata entry.
 			if metadata := nvdEntry.Metadata(); metadata != nil {
-				a.metadata[nvdEntry.Name] = *metadata
+				a.metadata[nvdEntry.Name()] = *metadata
 			}
 		}
 		f.Close()
@@ -154,7 +155,8 @@ func getDataFeeds(dataFeedHashes map[string]string, localPath string) (map[strin
 	// Create map containing the name and filename for every data feed.
 	dataFeedReaders := make(map[string]string)
 	for _, dataFeedName := range dataFeedNames {
-		fileName := filepath.Join(localPath, fmt.Sprintf("%s.xml", dataFeedName))
+		fileName := filepath.Join(localPath, fmt.Sprintf("%s.json", dataFeedName))
+
 		if h, ok := dataFeedHashes[dataFeedName]; ok && h == dataFeedHashes[dataFeedName] {
 			// The hash is known, the disk should contains the feed. Try to read from it.
 			if localPath != "" {
@@ -177,7 +179,6 @@ func getDataFeeds(dataFeedHashes map[string]string, localPath string) (map[strin
 }
 
 func downloadFeed(dataFeedName, fileName string) error {
-
 	// Download data feed.
 	r, err := httputil.GetWithUserAgent(fmt.Sprintf(dataFeedURL, dataFeedName))
 	if err != nil {