CVE-2026-46338
MediumCVSS 4.3Exploitation Probability (EPSS)
Low risk17th percentile - higher than 17% of all known CVEs
Summary
A vulnerability in PyMdown Extensions (versions 10.0.1 through 10.21.3) allows bypassing the base path restriction in the SnippetPreprocessor.get_snippet_path() function. The string-prefix containment check enables reading files from sibling directories sharing the same base_path prefix, representing a regression of the fix for CVE-2023-32309.
Risk Assessment
An attacker can exploit this flaw to read sensitive files outside the allowed base directory, potentially leading to disclosure of confidential data or application configuration.
Recommendation
Immediately upgrade PyMdown Extensions to version 10.21.3 or later, which includes a proper implementation of the base path restriction.
Other vulnerabilities in PyMdown Extensions
See all- CVE-2026-67422High
pymdown-extensions up to version 11.0 contains a vulnerability to catastrophic backtracking in four inline processors (caret, tilde, betterem, magiclink). A single untrusted Markdown line under 50 bytes can cause unbounded CPU usage, enabling a remote attacker to cause denial of service. The issue is fixed in version 11.0.1.
- CVE-2026-61632Medium
PyMdown Extensions is a set of extensions for the Python-Markdown markdown project. In versions up to and including 10.21.3, the b64 extension is vulnerable to a path traversal that discloses arbitrary files: it inlines images referenced by <img src="..."> by joining the src onto the configured base_path with os.path.normpath and opening the result directly, without verifying that the resolved path stays inside base_path. As a result, an src containing ../ sequences or an absolute path reads a file outside base_path as long as it has an allowed image extension (.png, .jpg, .jpeg, .gif, .svg), and the file's contents are then base64-encoded into the rendered output, disclosing them. This issue has been fixed in version 11.0.
Original NVD description (English source)
PyMdown Extensions is a set of extensions for the Python-Markdown markdown project. From 10.0.1 until 10.21.3, pymdownx.snippets uses a string-prefix containment check in SnippetPreprocessor.get_snippet_path() in pymdownx/snippets.py when `restrict_base_path: True`, allowing markdown snippet directives to read files from sibling paths that share the same base_path prefix, such as docs and docs_internal. This is a regression of CVE-2023-32309. This issue is fixed in version 10.21.3.