GHSA-77xj-x4rm-935c: datamodel-code-generator: Protobuf weak-import path traversal allows files to be written outside

When processing an attacker-controlled Protobuf schema, vulnerable versions of datamodel-code-generator could write a generated weak-import stub outside the intended __weak_imports__ temporary directory. Absolute import paths and relative paths containing .. could escape this directory. An attacker could create directories and new files at locations writable by the process. Relative path traversal could also overwrite existing writable files because the existence check and the stub write used different base directories. …