diff --git a/extensions/ql-vscode/package-lock.json b/extensions/ql-vscode/package-lock.json
index 086dc58ee68..d61638aca80 100644
--- a/extensions/ql-vscode/package-lock.json
+++ b/extensions/ql-vscode/package-lock.json
@@ -25,7 +25,7 @@
         "d3-graphviz": "^5.6.0",
         "fs-extra": "^11.1.1",
         "js-yaml": "^4.1.1",
-        "koffi": "^2.15.1",
+        "koffi": "^2.15.5",
         "msw": "^2.12.7",
         "nanoid": "^5.0.7",
         "p-queue": "^8.0.1",
@@ -20016,9 +20016,9 @@
       }
     },
     "node_modules/koffi": {
-      "version": "2.15.1",
-      "resolved": "https://registry.npmjs.org/koffi/-/koffi-2.15.1.tgz",
-      "integrity": "sha512-mnc0C0crx/xMSljb5s9QbnLrlFHprioFO1hkXyuSuO/QtbpLDa0l/uM21944UfQunMKmp3/r789DTDxVyyH6aA==",
+      "version": "2.15.5",
+      "resolved": "https://registry.npmjs.org/koffi/-/koffi-2.15.5.tgz",
+      "integrity": "sha512-4/35/oOpnH9tzrpWAC3ObjAERBSe0Q0Dh2NP1eBBPRGpohEj4vFw2+7tej9W9MTExvk0vtF0PjMqIGG4rf6feQ==",
       "hasInstallScript": true,
       "license": "MIT",
       "funding": {
diff --git a/extensions/ql-vscode/package.json b/extensions/ql-vscode/package.json
index 702e970bbba..0873a0e4bbb 100644
--- a/extensions/ql-vscode/package.json
+++ b/extensions/ql-vscode/package.json
@@ -2076,7 +2076,7 @@
     "@hpcc-js/wasm-graphviz": "^1.21.1",
     "fs-extra": "^11.1.1",
     "js-yaml": "^4.1.1",
-    "koffi": "^2.15.1",
+    "koffi": "^2.15.5",
     "msw": "^2.12.7",
     "nanoid": "^5.0.7",
     "p-queue": "^8.0.1",
diff --git a/extensions/ql-vscode/src/common/short-paths.ts b/extensions/ql-vscode/src/common/short-paths.ts
index 860544c38d4..3f6698d7ec6 100644
--- a/extensions/ql-vscode/src/common/short-paths.ts
+++ b/extensions/ql-vscode/src/common/short-paths.ts
@@ -170,7 +170,7 @@ async function expandShortPathNative(shortPath: string, logger: BaseLogger) {
     throw new Error("Failed to get long path name");
   }
 
-  const longPath = buffer.toString("utf16le", 0, (result - 1) * 2);
+  const longPath = buffer.toString("utf16le", 0, result * 2);
 
   void logger.log(`Expanded short path ${shortPath} to ${longPath}`);