Improve path traversal security vulnerability (#6138)

Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

docs/hub/app/android.md

@@ -39,7 +39,7 @@ Here's a table showing the primary vendors, their product lines, popular devices
 |-----------------------------------------|--------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------|
 | [Qualcomm](https://www.qualcomm.com/)   | [Snapdragon (e.g., 800 series)](https://www.qualcomm.com/snapdragon)                 | [Samsung Galaxy S21](https://www.samsung.com/global/galaxy/galaxy-s21-5g/), [OnePlus 9](https://www.oneplus.com/9), [Google Pixel 6](https://store.google.com/product/pixel_6) | CPU, GPU, Hexagon, NNAPI |
 | [Samsung](https://www.samsung.com/)     | [Exynos (e.g., Exynos 2100)](https://www.samsung.com/semiconductor/minisite/exynos/) | [Samsung Galaxy S21 (Global version)](https://www.samsung.com/global/galaxy/galaxy-s21-5g/)                                                                                    | CPU, GPU, NNAPI          |
-| [MediaTek](https://www.mediatek.com/)   | [Dimensity (e.g., Dimensity 1200)](https://www.mediatek.com/products/smartphones)    | [Realme GT](https://www.realme.com/global/realme-gt), [Xiaomi Redmi Note](https://www.mi.com/en/phone/redmi/note-list)                                                         | CPU, GPU, NNAPI          |
+| [MediaTek](https://i.mediatek.com/)     | [Dimensity (e.g., Dimensity 1200)](https://i.mediatek.com/dimensity-1200)            | [Realme GT](https://www.realme.com/global/realme-gt), [Xiaomi Redmi Note](https://www.mi.com/en/phone/redmi/note-list)                                                         | CPU, GPU, NNAPI          |
 | [HiSilicon](https://www.hisilicon.com/) | [Kirin (e.g., Kirin 990)](https://www.hisilicon.com/en/products/Kirin)               | [Huawei P40 Pro](https://consumer.huawei.com/en/phones/p40-pro/), [Huawei Mate 30 Pro](https://consumer.huawei.com/en/phones/mate30-pro/)                                      | CPU, GPU, NNAPI          |
 | [NVIDIA](https://www.nvidia.com/)       | [Tegra (e.g., Tegra X1)](https://developer.nvidia.com/content/tegra-x1)              | [NVIDIA Shield TV](https://www.nvidia.com/en-us/shield/shield-tv/), [Nintendo Switch](https://www.nintendo.com/switch/)                                                        | CPU, GPU, NNAPI          |
 

docs/reference/utils/checks.md

@@ -61,6 +61,10 @@ keywords: Ultralytics, utility checks, ASCII, check_version, pip_update, check_p
 ## ::: ultralytics.utils.checks.check_yolov5u_filename
 <br><br>
 
+---
+## ::: ultralytics.utils.checks.check_model_file_from_stem
+<br><br>
+
 ---
 ## ::: ultralytics.utils.checks.check_file
 <br><br>
@@ -69,6 +73,10 @@ keywords: Ultralytics, utility checks, ASCII, check_version, pip_update, check_p
 ## ::: ultralytics.utils.checks.check_yaml
 <br><br>
 
+---
+## ::: ultralytics.utils.checks.check_is_path_safe
+<br><br>
+
 ---
 ## ::: ultralytics.utils.checks.check_imshow
 <br><br>

ultralytics/engine/exporter.py

@@ -69,7 +69,7 @@ from ultralytics.nn.modules import C2f, Detect, RTDETRDecoder
 from ultralytics.nn.tasks import DetectionModel, SegmentationModel
 from ultralytics.utils import (ARM64, DEFAULT_CFG, LINUX, LOGGER, MACOS, ROOT, WINDOWS, __version__, callbacks,
                                colorstr, get_default_args, yaml_save)
-from ultralytics.utils.checks import check_imgsz, check_requirements, check_version
+from ultralytics.utils.checks import check_imgsz, check_is_path_safe, check_requirements, check_version
 from ultralytics.utils.downloads import attempt_download_asset, get_github_assets
 from ultralytics.utils.files import file_size, spaces_in_path
 from ultralytics.utils.ops import Profile
@@ -450,12 +450,9 @@ class Exporter:
         f = Path(str(self.file).replace(self.file.suffix, f'_ncnn_model{os.sep}'))
         f_ts = self.file.with_suffix('.torchscript')
 
-        pnnx_filename = 'pnnx.exe' if WINDOWS else 'pnnx'
+        name = Path('pnnx.exe' if WINDOWS else 'pnnx')  # PNNX filename
-        if Path(pnnx_filename).is_file():
+        pnnx = name if name.is_file() else ROOT / name
-            pnnx = pnnx_filename
+        if not pnnx.is_file():
-        elif (ROOT / pnnx_filename).is_file():
-            pnnx = ROOT / pnnx_filename
-        else:
             LOGGER.warning(
                 f'{prefix} WARNING ⚠️ PNNX not found. Attempting to download binary file from '
                 'https://github.com/pnnx/pnnx/.\nNote PNNX Binary file must be placed in current working directory '
@@ -465,12 +462,12 @@ class Exporter:
             asset = [x for x in assets if system in x][0] if assets else \
                 f'https://github.com/pnnx/pnnx/releases/download/20230816/pnnx-20230816-{system}.zip'  # fallback
             asset = attempt_download_asset(asset, repo='pnnx/pnnx', release='latest')
-            unzip_dir = Path(asset).with_suffix('')
+            if check_is_path_safe(Path.cwd(), asset):  # avoid path traversal security vulnerability
-            pnnx = ROOT / pnnx_filename  # new location
+                unzip_dir = Path(asset).with_suffix('')
-            (unzip_dir / pnnx_filename).rename(pnnx)  # move binary to ROOT
+                (unzip_dir / name).rename(pnnx)  # move binary to ROOT
-            shutil.rmtree(unzip_dir)  # delete unzip dir
+                shutil.rmtree(unzip_dir)  # delete unzip dir
-            Path(asset).unlink()  # delete zip
+                Path(asset).unlink()  # delete zip
-            pnnx.chmod(0o777)  # set read, write, and execute permissions for everyone
+                pnnx.chmod(0o777)  # set read, write, and execute permissions for everyone
 
         ncnn_args = [
             f'ncnnparam={f / "model.ncnn.param"}',

ultralytics/utils/checks.py

@@ -463,6 +463,23 @@ def check_yaml(file, suffix=('.yaml', '.yml'), hard=True):
     return check_file(file, suffix, hard=hard)
 
 
+def check_is_path_safe(basedir, path):
+    """
+    Check if the resolved path is under the intended directory to prevent path traversal.
+
+    Args:
+        basedir (Path | str): The intended directory.
+        path (Path | str): The path to check.
+
+    Returns:
+        (bool): True if the path is safe, False otherwise.
+    """
+    base_dir_resolved = Path(basedir).resolve()
+    path_resolved = Path(path).resolve()
+
+    return path_resolved.is_file() and path_resolved.parts[:len(base_dir_resolved.parts)] == base_dir_resolved.parts
+
+
 def check_imshow(warn=False):
     """Check if environment supports image displays."""
     try:

ultralytics/utils/downloads.py

@@ -159,7 +159,11 @@ def unzip_file(file, path=None, exclude=('.DS_Store', '__MACOSX'), exist_ok=Fals
             return path
 
         for f in TQDM(files, desc=f'Unzipping {file} to {Path(path).resolve()}...', unit='file', disable=not progress):
-            zipObj.extract(f, path=extract_path)
+            # Ensure the file is within the extract_path to avoid path traversal security vulnerability
+            if '..' in Path(f).parts:
+                LOGGER.warning(f'Potentially insecure file path: {f}, skipping extraction.')
+                continue
+            zipObj.extract(f, extract_path)
 
     return path  # return unzip dir