PyMdown Extensions up to 9.x path traversal

Summaryinfo

A vulnerability labeled as critical has been found in PyMdown Extensions up to 9.x. The affected element is an unknown function. The manipulation results in path traversal. This vulnerability is reported as CVE-2023-32309. The attack can be launched remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in PyMdown Extensions up to 9.x. It has been classified as critical. Affected is an unknown part. The manipulation with an unknown input leads to a path traversal vulnerability. CWE is classifying the issue as CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. This is going to have an impact on confidentiality. CVE summarizes:

PyMdown Extensions is a set of extensions for the `Python-Markdown` markdown project. In affected versions an arbitrary file read is possible when using include file syntax. By using the syntax `--8<--"/etc/passwd"` or `--8<--"/proc/self/environ"` the content of these files will be rendered in the generated documentation. Additionally, a path relative to a specified, allowed base path can also be used to render the content of a file outside the specified base paths: `--8<-- "../../../../etc/passwd"`. Within the Snippets extension, there exists a `base_path` option but the implementation is vulnerable to Directory Traversal. The vulnerable section exists in `get_snippet_path(self, path)` lines 155 to 174 in snippets.py. Any readable file on the host where the plugin is executing may have its content exposed. This can impact any use of Snippets that exposes the use of Snippets to external users. It is never recommended to use Snippets to process user-facing, dynamic content. It is designed to process known content on the backend under the control of the host, but if someone were to accidentally enable it for user-facing content, undesired information could be exposed. This issue has been addressed in version 10.0. Users are advised to upgrade. Users unable to upgrade may restrict relative paths by filtering input.

The weakness was disclosed 05/16/2023 as GHSA-jh85-wwv9-24hv. The advisory is shared for download at github.com. This vulnerability is traded as CVE-2023-32309 since 05/08/2023. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1006.

Upgrading to version 10.0 eliminates this vulnerability. Applying the patch b7bb4878d6017c03c8dc97c42d8d3bb6ee81db9d is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

• PyMdown Extensions

Version

• 9.x

License

• open-source

CPE 2.3info

• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍

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Once again VulDB remains the best source for vulnerability data.

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