fix: guard against undefined technique references when building detection mappings

Author: clemiller

CHANGELOG.md

@@ -8,6 +8,11 @@
     This will patch the version number appropriately and create the correct tag on the current commit.
     The creation of the tag can be disabled with the --no-git-tag-version if desired.
 -->
+# 5.3.2 - 21 April 2026
+
+## Fixes
+- Fixed an issue preventing the matrix from building if a detection mapping had no technique references.
+
 
 # 5.3.1 - 6 April 2026
 

nav-app/package-lock.json

@@ -5,7 +5,7 @@
     "type": "git",
     "url": "https://github.com/mitre-attack/attack-navigator.git"
   },
-  "version": "5.3.1",
+  "version": "5.3.2",
   "license": "Apache-2.0",
   "scripts": {
     "ng": "ng",

nav-app/package.json

@@ -232,7 +232,7 @@ export class DataService {
     public buildDataComponentToTechniquesMap(domain: Domain, analytics: any[]) {
         for (let det of domain.detectionStrategies) {
             let techniqueRefs = domain.relationships.detection_strategies_detect.get(det.id);
-            let techniqueRef = techniqueRefs.length > 0 ? techniqueRefs[0] : undefined; // should only be one
+            let techniqueRef = techniqueRefs?.length > 0 ? techniqueRefs[0] : undefined; // should only be one
             const technique = domain.getTechniqueById(techniqueRef);
             if (!technique) continue; // no technique found, skip
             for (let analytic_ref of det.analyticRefs) {