Vulnerability processing should ignore software without version (#14612)

#13615

- [X] Changes file added for user-visible changes in `changes/` or
`orbit/changes/`.
See [Changes
files](https://fleetdm.com/docs/contributing/committing-changes#changes-files)
for more information.
- ~[ ] Documented any API changes (docs/Using-Fleet/REST-API.md or
docs/Contributing/API-for-contributors.md)~
- ~[ ] Documented any permissions changes (docs/Using
Fleet/manage-access.md)~
- ~[ ] Input data is properly validated, `SELECT *` is avoided, SQL
injection is prevented (using placeholders for values in statements)~
- ~[ ] Added support on fleet's osquery simulator `cmd/osquery-perf` for
new osquery data ingestion features.~
- [X] Added/updated tests
- [X] Manual QA for all new/changed functionality
  - ~For Orbit and Fleet Desktop changes:~
- ~[ ] Manual QA must be performed in the three main OSs, macOS, Windows
and Linux.~
- ~[ ] Auto-update manual QA, from released version of component to new
version (see [tools/tuf/test](../tools/tuf/test/README.md)).~

changes/13615-ignore-software-without-version

@@ -0,0 +1 @@
+* Updated vulnerability processing to ignore software that has been ingested without a version.

docs/Using Fleet/Vulnerability-Processing.md

@@ -301,6 +301,8 @@ With a somewhat normalized list of software, in order to search CVEs for it, we
 
 As described briefly above, we do this by translating the NVD database of CPEs into a [sqlite database that helps Fleet do the lookup of CPEs very quickly](https://github.com/fleetdm/nvd).
 
+NOTE: Software that was ingested with an empty `version` field will be ignored by the NVD vulnerability processing.
+
 #### How accurate is this translation process?
 
 This is the most error prone part of the process.

server/vulnerabilities/nvd/cpe.go

@@ -397,12 +397,33 @@ func TranslateSoftwareToCPE(
 		if err != nil {
 			return ctxerr.Wrap(ctx, err, "getting value from iterator")
 		}
-		cpe, err := CPEFromSoftware(db, software, cpeTranslations, reCache)
+		var cpe string
+		// Skip software without version to avoid false positives in the CPE
+		// matching process.
+		if software.Version == "" {
+			level.Debug(logger).Log(
+				"msg", "skipping software without version",
+				"software", software.Name,
+				"source", software.Source,
+			)
+			// We want to continue here in case the software had an invalid CPE
+			// generated by a previous version of Fleet.
+		} else {
+			cpe, err = CPEFromSoftware(db, software, cpeTranslations, reCache)
 			if err != nil {
-			level.Error(logger).Log("software->cpe", "error translating to CPE, skipping...", "err", err)
+				level.Error(logger).Log(
+					"msg", "error translating to CPE, skipping",
+					"software", software.Name,
+					"version", software.Version,
+					"source", software.Source,
+					"err", err,
+				)
 				continue
 			}
+		}
 		if cpe == software.GenerateCPE {
+			// If the generated CPE hasn't changed from what's already stored in the DB
+			// then we don't need to do anything.
 			continue
 		}
 

server/vulnerabilities/nvd/cpe_test.go

@@ -297,8 +297,6 @@ func TestConsumeCPEBuffer(t *testing.T) {
 }
 
 func TestTranslateSoftwareToCPE(t *testing.T) {
-	nettest.Run(t)
-
 	tempDir := t.TempDir()
 
 	ds := new(mock.Store)
@@ -361,6 +359,52 @@ func TestTranslateSoftwareToCPE(t *testing.T) {
 	assert.True(t, iterator.closed)
 }
 
+// TestTranslateSoftwareToCPEIgnoreEmptyVersion tests that TranslateSoftwareToCPE ignores
+// software that was ingested with an empty version field. The test will simulate a previous
+// version of Fleet storing an incorrect CPE for the software, to test that an upgrade
+// will clear out the invalid CPE from the DB.
+func TestTranslateSoftwareToCPEIgnoreEmptyVersion(t *testing.T) {
+	tempDir := t.TempDir()
+
+	ds := new(mock.Store)
+
+	// The incorrect CPE for the software should now be deleted because the ingested software doesn't
+	// have a version field.
+	ds.DeleteSoftwareCPEsFunc = func(ctx context.Context, cpes []fleet.SoftwareCPE) (int64, error) {
+		require.Len(t, cpes, 1)
+		require.Equal(t, cpes[0].SoftwareID, uint(1))
+		return 1, nil
+	}
+
+	ds.AllSoftwareIteratorFunc = func(ctx context.Context, q fleet.SoftwareIterQueryOptions) (fleet.SoftwareIterator, error) {
+		return &fakeSoftwareIterator{
+			softwares: []*fleet.Software{
+				{
+					ID:               1,
+					Name:             "foobar",
+					Version:          "",
+					BundleIdentifier: "vendor2",
+					Source:           "apps",
+					// Set an incorrect CPE on the DB to simulate a CPE being generated incorrectly
+					// for this software on a previous version of Fleet.
+					GenerateCPE: "cpe:2.3:a:vendor2:foobar:*:*:*:*:*:macos:*:*",
+				},
+			},
+		}, nil
+	}
+
+	items, err := cpedict.Decode(strings.NewReader(XmlCPETestDict))
+	require.NoError(t, err)
+
+	dbPath := filepath.Join(tempDir, "cpe.sqlite")
+	err = GenerateCPEDB(dbPath, items)
+	require.NoError(t, err)
+
+	err = TranslateSoftwareToCPE(context.Background(), ds, tempDir, kitlog.NewNopLogger())
+	require.NoError(t, err)
+	require.True(t, ds.DeleteSoftwareCPEsFuncInvoked)
+}
+
 func TestSyncsCPEFromURL(t *testing.T) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		zw := gzip.NewWriter(w)