fix: reject path traversal in python entrypoints#2445
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baszalmstra merged 1 commit intoMay 19, 2026
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…points `EntryPoint::FromStr` in `rattler_conda_types` previously only trimmed whitespace before the linker joined `command` onto the install prefix and wrote an executable Python script at `<prefix>/<bin_dir>/<command>` (with `-script.py` / `.exe` siblings on Windows). A malicious `noarch:python` package could ship `info/link.json` with an entry-point name containing `..`, `/`, `\`, or an absolute path, causing the resulting file to be written outside the prefix or clobber an in-prefix entry-point such as `bin/pip`. The renderer also interpolated `module` and `function` verbatim into the generated script body, giving a second code-injection surface. This change adds validation at two layers: * `EntryPoint::FromStr` now validates `command` as a simple file name (rejecting empty strings, `/`, `\`, `\0`, `.`, `..`, leading `.`, and absolute paths) and `module` / `function` as Python dotted identifiers. Errors are returned via a typed `ParseEntryPointError` enum (with a companion `EntryPointDottedField`) instead of bare strings. Both are re-exported from `rattler_conda_types::package`. * The install crate gains a `ValidatedRelativePath` newtype whose only constructor is `ensure_entry_point_relative_path`, which performs component-wise normalization and verifies that the resolved path stays under the install prefix. All filesystem-write helpers in `install::entry_point` (`write_validated_entry_point_file`, `write_validated_entry_point_bytes` for the Windows launcher, and `set_validated_entry_point_executable` for the Unix +x bit) take `&ValidatedRelativePath`, so the compiler rejects any call site that would reach a write without having run validation first. Tested via new unit tests covering the traversal vectors from the report (`../bin/pip`, absolute `/tmp/PWN`, Windows `..\..\..\`, hidden names, NUL byte), code-injection attempts in `module`/`function`, and realistic legitimate names (`jupyter-lab`, `pip3.11`, `pkg:Class.method`, `_private`). https://claude.ai/code/session_01RhMEEcinYyVNw9YtZTHqwR
pavelzw
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May 19, 2026
baszalmstra
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Fixes GHSA-q53q-5r4j-5729