pdm is a Python package and dependency manager supporting the latest PEP standards. Versions prior to 2.27.0 are vulnerable to path traversal through write_to_fs. InstallDestination.write_to_fs() in src/pdm/installers/installers.py overrides the base class to add symlink/hardlink support but replaces the safe _path_with_destdir() (which validates via Path.resolve() + is_relative_to()) with a bare os.path.join() that performs no path validation. A malicious wheel with traversal entries can write arbitrary files. This issue has been fixed in version 2.27.0.

PDM is a Python package and dependency manager. In versions up to and including 2.26.9, PDM automatically loads project-local plugins from a .pdm-plugins directory during initialization, allowing an attacker-controlled file in an untrusted repository checkout to execute arbitrary Python code before any command is parsed. This happens because load_plugins() runs during Core.init() and adds .pdm-plugins via site.addsitedir(), which processes .pth files and immediately executes any line beginning with import, so the code runs with the privileges of the user invoking pdm and even a benign command such as pdm --version triggers it (making the impact strongest in CI, automation, and privileged contexts). The issue is fixed in version 2.27.0.

pdm is a Python package and dependency manager supporting the latest PEP standards. In versions prior to 2.27.0, pdm writes several project-local state or configuration files without symlink protection. If a malicious repository places those files as symlinks, local PDM operations can overwrite the symlink targets. This creates an arbitrary file clobber primitive relative to the privileges of the invoking user. Config.__init__() resolves the project-local pdm.toml path and _save_config() writes to the resolved target. If PROJECT_ROOT/pdm.toml is a symlink to another file, pdm config -l ... updates the target file instead of refusing the write. The same general problem exists for other project-local persistence paths that are written directly with no lstat / O_NOFOLLOW protection. For the pdm.toml PoC specifically, the target file must already contain parseable TOML. Otherwise the load step fails before the write path is reached. That parser constraint does not apply to the .pdm-python or .python-version sinks. This issue has been fixed in version 2.27.0.