Launch Week Day 1: Announcing Security Design Review
HIGH 7.1 PyPI

pyLoad has an Arbitrary File Write via Path Traversal in edit_package()

GHSA-6px9-j4qr-xfjw · CVE-2026-29778 · PYSEC-2026-121

Published · Modified

Description

The edit_package() function implements insufficient sanitization for the pack_folder parameter. The current protection relies on a single-pass string replacement of "../", which can be bypassed using crafted recursive traversal sequences.

Exploitation

An authenticated user with MODIFY permission can bypass the sanitization by submitting a payload such as:
pack_folder=..././..././..././tmp

After the single-pass replacement, this becomes:
../../../tmp

Because the traversal sequences are not properly validated, the resulting normalized path escapes the intended storage directory and writes files to /tmp or other locations.

Ready to move

Start Securing

Free, no credit card | First findings in minutes