diff --git a/src/f5_tts/train/finetune_gradio.py b/src/f5_tts/train/finetune_gradio.py
index 692c95c..3acfec3 100644
--- a/src/f5_tts/train/finetune_gradio.py
+++ b/src/f5_tts/train/finetune_gradio.py
@@ -33,6 +33,22 @@ from f5_tts.infer.utils_infer import transcribe
 from f5_tts.model.utils import convert_char_to_pinyin
 
 
+def _safe_project_path(base: str, name: str) -> str:
+    """Return the resolved absolute path of base/name, raising ValueError if name
+    is absolute, contains a null byte, or resolves outside base."""
+    if not name or os.path.isabs(name) or "\x00" in name:
+        raise ValueError(f"invalid project_name: {name!r}")
+    # Strip path separators and control characters to a plain filename component.
+    name = re.sub(r"[/\\]", "", name).strip()
+    if not name or name in (".", ".."):
+        raise ValueError(f"invalid project_name: {name!r}")
+    candidate = os.path.realpath(os.path.join(base, name))
+    base_real = os.path.realpath(base)
+    if not (candidate + os.sep).startswith(base_real + os.sep):
+        raise ValueError(f"project_name escapes base directory: {name!r}")
+    return candidate
+
+
 training_process = None
 system = platform.system()
 python_executable = sys.executable or "python"
@@ -80,7 +96,7 @@ def save_settings(
     logger,
     ch_8bit_adam,
 ):
-    path_project = os.path.join(path_project_ckpts, project_name)
+    path_project = _safe_project_path(path_project_ckpts, project_name)
     os.makedirs(path_project, exist_ok=True)
     file_setting = os.path.join(path_project, "setting.json")
 
@@ -113,7 +129,7 @@ def save_settings(
 # Load settings from a JSON file
 def load_settings(project_name):
     project_name = project_name.replace("_pinyin", "").replace("_char", "")
-    path_project = os.path.join(path_project_ckpts, project_name)
+    path_project = _safe_project_path(path_project_ckpts, project_name)
     file_setting = os.path.join(path_project, "setting.json")
 
     # Default settings
@@ -356,7 +372,7 @@ def start_training(
         torch.cuda.empty_cache()
         tts_api = None
 
-    path_project = os.path.join(path_data, dataset_name)
+    path_project = _safe_project_path(path_data, dataset_name)
 
     if not os.path.isdir(path_project):
         yield (
@@ -610,14 +626,15 @@ def get_list_projects():
 
 def create_data_project(name, tokenizer_type):
     name += "_" + tokenizer_type
-    os.makedirs(os.path.join(path_data, name), exist_ok=True)
-    os.makedirs(os.path.join(path_data, name, "dataset"), exist_ok=True)
+    project_dir = _safe_project_path(path_data, name)
+    os.makedirs(project_dir, exist_ok=True)
+    os.makedirs(os.path.join(project_dir, "dataset"), exist_ok=True)
     project_list, projects_selelect = get_list_projects()
     return gr.update(choices=project_list, value=name)
 
 
 def transcribe_all(name_project, audio_files, language, user=False, progress=gr.Progress()):
-    path_project = os.path.join(path_data, name_project)
+    path_project = _safe_project_path(path_data, name_project)
     path_dataset = os.path.join(path_project, "dataset")
     path_project_wavs = os.path.join(path_project, "wavs")
     file_metadata = os.path.join(path_project, "metadata.csv")
@@ -726,7 +743,7 @@ def get_correct_audio_path(
 
 
 def create_metadata(name_project, ch_tokenizer, progress=gr.Progress()):
-    path_project = os.path.join(path_data, name_project)
+    path_project = _safe_project_path(path_data, name_project)
     path_project_wavs = os.path.join(path_project, "wavs")
     file_metadata = os.path.join(path_project, "metadata.csv")
     file_raw = os.path.join(path_project, "raw.arrow")
@@ -850,7 +867,7 @@ def calculate_train(
     num_warmup_updates,
     finetune,
 ):
-    path_project = os.path.join(path_data, name_project)
+    path_project = _safe_project_path(path_data, name_project)
     file_duration = os.path.join(path_project, "duration.json")
 
     hop_length = 256
@@ -1003,7 +1020,7 @@ def vocab_extend(project_name, symbols, model_type):
         return "Symbols empty!"
 
     name_project = project_name
-    path_project = os.path.join(path_data, name_project)
+    path_project = _safe_project_path(path_data, name_project)
     file_vocab_project = os.path.join(path_project, "vocab.txt")
 
     file_vocab = os.path.join(path_data, "Emilia_ZH_EN_pinyin/vocab.txt")
@@ -1049,7 +1066,7 @@ def vocab_extend(project_name, symbols, model_type):
     vocab_size_new = len(miss_symbols)
 
     dataset_name = name_project.replace("_pinyin", "").replace("_char", "")
-    new_ckpt_path = os.path.join(path_project_ckpts, dataset_name)
+    new_ckpt_path = _safe_project_path(path_project_ckpts, dataset_name)
     os.makedirs(new_ckpt_path, exist_ok=True)
 
     # Add pretrained_ prefix to model when copying for consistency with finetune_cli.py
@@ -1063,7 +1080,7 @@ def vocab_extend(project_name, symbols, model_type):
 
 def vocab_check(project_name, tokenizer_type):
     name_project = project_name
-    path_project = os.path.join(path_data, name_project)
+    path_project = _safe_project_path(path_data, name_project)
 
     file_metadata = os.path.join(path_project, "metadata.csv")
 
@@ -1110,7 +1127,7 @@ def vocab_check(project_name, tokenizer_type):
 
 def get_random_sample_prepare(project_name):
     name_project = project_name
-    path_project = os.path.join(path_data, name_project)
+    path_project = _safe_project_path(path_data, name_project)
     file_arrow = os.path.join(path_project, "raw.arrow")
     if not os.path.isfile(file_arrow):
         return "", None
@@ -1123,7 +1140,7 @@ def get_random_sample_prepare(project_name):
 
 def get_random_sample_transcribe(project_name):
     name_project = project_name
-    path_project = os.path.join(path_data, name_project)
+    path_project = _safe_project_path(path_data, name_project)
     file_metadata = os.path.join(path_project, "metadata.csv")
     if not os.path.isfile(file_metadata):
         return "", None