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. An application that renders untrusted Markdown with pymdownx.b64 enabled can therefore leak the contents of image-extension files readable by the process to whoever controls the Markdown or views the output, a targeted file-read bounded by the extension check. This issue has been fixed in version 11.0.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - 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. An application that renders untrusted
    Markdown with pymdownx.b64 enabled can therefore leak the contents of image-extension files readable by
    the process to whoever controls the Markdown or views the output, a targeted file-read bounded by the
    extension check. This issue has been fixed in version 11.0. (CVE-2026-61632)

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - 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. An application that renders untrusted     Markdown with pymdownx.b64 enabled can therefore leak the contents of image-extension files readable by     the process to whoever controls the Markdown or views the output, a targeted file-read bounded by the     extension check. This issue has been fixed in version 11.0. (CVE-2026-61632)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
462924	Echo: pymdown-extensions: security update to 11.0.0	Tenable Cloud Security	Echo Local Security Checks	Local	medium
462924	Echo: pymdown-extensions: security update to 11.0.0	Tenable Self-Hosted Container Security	Echo Local Security Checks	Local	medium
333365	Linux Distros Unpatched Vulnerability : CVE-2026-61632	Nessus	Misc.	Local	medium
445281	SCA: security update for pymdown-extensions (GHSA-9xwg-3r6f-jcx2)	Tenable Cloud Security	SCA Checks	Local	medium
445281	SCA: security update for pymdown-extensions (GHSA-9xwg-3r6f-jcx2)	Tenable Self-Hosted Container Security	SCA Checks	Local	medium

Detections

Analytics

CVE-2026-61632

medium

Tenable Plugins

medium

medium

medium

medium

medium