CVE-2023-40587 Information

Description

Pyramid is an open source Python web framework. A path traversal vulnerability in Pyramid versions 2.0.0 and 2.0.1 impacts users of Python 3.11 that are using a Pyramid static view with a full filesystem path and have a index.html file that is located exactly one directory above the location of the static view’s file system path. No further path traversal exists and the only file that could be disclosed accidentally is index.html. Pyramid version 2.0.2 rejects any path that contains a null-byte out of caution. While valid in directory/file names we would strongly consider it a mistake to use null-bytes in naming files/directories. Secondly Python 3.11 and 3.12 has fixed the underlying issue in os.path.normpath to no longer truncate on the first 0x00 found returning the behavior to pre-3.11 Python un an as of yet unreleased version. Fixes will be available in:Python 3.12.0rc2 and 3.11.5. Some workarounds are available. Use a version of Python 3 that is not affected downgrade to Python 3.10 series temporarily or wait until Python 3.11.5 is released and upgrade to the latest version of Python 3.11 series.

Reference

https://github.com/Pylons/pyramid/commit/347d7750da6f45c7436dd0c31468885cc9343c85 https://github.com/python/cpython/issues/106242 https://github.com/python/cpython/pull/106816 https://github.com/Pylons/pyramid/security/advisories/GHSA-j8g2-6fc7-q8f8