diff --git a/lib/entry-points.js b/lib/entry-points.js
index ebe7f9d17..d9047f677 100644
--- a/lib/entry-points.js
+++ b/lib/entry-points.js
@@ -170762,7 +170762,7 @@ function createApiClientWithDetails(apiDetails, { allowExternal = false, proxy =
   const retryingOctokit = githubUtils.GitHub.plugin(retry);
   const requestOptions = makeProxyRequestOptions(proxy);
   const opts = {
-    auth: auth2 !== void 0 ? `token ${auth2}` : void 0,
+    auth: auth2 !== void 0 && auth2.trim() !== "" ? `token ${auth2}` : void 0,
     baseUrl: apiDetails.apiURL,
     userAgent: `CodeQL-Action/${getActionVersion()}`,
     log: {
diff --git a/src/api-client.ts b/src/api-client.ts
index 31169480a..4d0a99920 100644
--- a/src/api-client.ts
+++ b/src/api-client.ts
@@ -138,7 +138,8 @@ function createApiClientWithDetails(
   const requestOptions = makeProxyRequestOptions(proxy);
 
   const opts: OctokitOptions = {
-    auth: auth !== undefined ? `token ${auth}` : undefined,
+    auth:
+      auth !== undefined && auth.trim() !== "" ? `token ${auth}` : undefined,
     baseUrl: apiDetails.apiURL,
     userAgent: `CodeQL-Action/${getActionVersion()}`,
     log: {