diff --git a/packages/hydrooj/package.json b/packages/hydrooj/package.json
index b625e1859..d85666264 100644
--- a/packages/hydrooj/package.json
+++ b/packages/hydrooj/package.json
@@ -1,6 +1,6 @@
 {
     "name": "hydrooj",
-    "version": "2.15.22",
+    "version": "2.15.23",
     "bin": "bin/hydrooj.js",
     "main": "dist/loader.js",
     "typings": "dist/loader.d.ts",
diff --git a/packages/hydrooj/src/handler/import.syzoj.ts b/packages/hydrooj/src/handler/import.syzoj.ts
index c8ed04199..f3c255dfa 100644
--- a/packages/hydrooj/src/handler/import.syzoj.ts
+++ b/packages/hydrooj/src/handler/import.syzoj.ts
@@ -18,7 +18,7 @@ import storage from '../service/storage';
 import { isPid } from '../lib/validator';
 import download from '../lib/download';
 
-const RE_SYZOJ = /(https?):\/\/([a-zA-Z0-9.:]+)\/(problem|p)\/([0-9]+)\/?/i;
+const RE_SYZOJ = /(https?):\/\/([^/]+)\/(problem|p)\/([0-9]+)\/?/i;
 const logger = new Logger('import.syzoj');
 
 class ProblemImportSYZOJHandler extends Handler {
@@ -112,11 +112,12 @@ class ProblemImportSYZOJHandler extends Handler {
             // eslint-disable-next-line no-await-in-loop
             await problem.addTestdata(domainId, docId, entry.entryName, entry.getData());
         }
+        const filename = p.file_io_input_name ? p.file_io_input_name?.split('.')[0] : null;
         await problem.edit(domainId, docId, {
             config: {
                 time: `${p.time_limit}ms`,
                 memory: `${p.memory_limit}m`,
-                filename: p.file_io_input_name.split('.')[0],
+                filename,
                 type: p.type === 'traditional' ? 'default' : p.type,
             },
         });