Mistune is a Python Markdown parser with renderers and plugins. In 3.2.0 and earlier, in src/mistune/directives/image.py, the render_figure() function concatenates figclass and figwidth options directly into HTML attributes without escaping. This allows attribute injection and XSS even when HTMLRenderer(escape=True) is used, because these values bypass the inline renderer. Version 3.2.1 contains a patch.

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

  - Mistune is a Python Markdown parser with renderers and plugins. In 3.2.0 and earlier, in
    src/mistune/directives/image.py, the render_figure() function concatenates figclass and figwidth options
    directly into HTML attributes without escaping. This allows attribute injection and XSS even when
    HTMLRenderer(escape=True) is used, because these values bypass the inline renderer. Version 3.2.1 contains
    a patch. (CVE-2026-44896)

An update of the python3 package has been released.

The remote SUSE Linux SLES16 / SLES_SAP16 host has a package installed that is affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:22655-1 advisory.

    This update for python-mistune fixes the following issues

    - CVE-2026-59922: quadratic-time parsing on long runs of some markers in `formatting.py` can lead to DoS     (bsc#1271117).
    - CVE-2026-59923: `HTMLRenderer.safe_url()` does not block percent-encoded javascript URIs and allows for     XSS       (bsc#1271119).
    - CVE-2026-59924: improper processing of user-supplied include paths in `Include.parse()` can lead to path     traversal       and arbitrary file reads (bsc#1271121).
    - CVE-2026-59925: quadratic-time parsing on long runs of some emphasis pairs in `inline_parser` can lead     to DoS       (bsc#1271125).
    - CVE-2026-59926: improper escaping in `render_admonition()` can lead to atribute injection and XSS     (bsc#1271127).
    - CVE-2026-59927: uncontrolled recursion when processing two markdown files that include each other can     lead to a DoS        (bsc#1271128).
    - CVE-2026-59928: quadratic-time parsing on long lists of repeated reference-link definitions in     `block_parser` can       lead to DoS (bsc#1271131).
    - CVE-2026-59929: HARMFUL_PROTOCOLS list misses legacy and chained schemes and allow arbitrary script     execution in       user agents (bsc#1271132).
    - CVE-2026-59930: the `toc` plugin and `TableOfContents` directive generate heading IDs with predictable     values and       allow for collisions with attacker-controlled `id=toc_N` content (bsc#1271082).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote openSUSE 16 host has a package installed that is affected by multiple vulnerabilities as referenced in the openSUSE-SU-2026:21339-1 advisory.

    This update for python-mistune fixes the following issues

    - CVE-2026-59922: quadratic-time parsing on long runs of some markers in `formatting.py` can lead to DoS     (bsc#1271117).
    - CVE-2026-59923: `HTMLRenderer.safe_url()` does not block percent-encoded javascript URIs and allows for     XSS       (bsc#1271119).
    - CVE-2026-59924: improper processing of user-supplied include paths in `Include.parse()` can lead to path     traversal       and arbitrary file reads (bsc#1271121).
    - CVE-2026-59925: quadratic-time parsing on long runs of some emphasis pairs in `inline_parser` can lead     to DoS       (bsc#1271125).
    - CVE-2026-59926: improper escaping in `render_admonition()` can lead to atribute injection and XSS     (bsc#1271127).
    - CVE-2026-59927: uncontrolled recursion when processing two markdown files that include each other can     lead to a DoS        (bsc#1271128).
    - CVE-2026-59928: quadratic-time parsing on long lists of repeated reference-link definitions in     `block_parser` can       lead to DoS (bsc#1271131).
    - CVE-2026-59929: HARMFUL_PROTOCOLS list misses legacy and chained schemes and allow arbitrary script     execution in       user agents (bsc#1271132).
    - CVE-2026-59930: the `toc` plugin and `TableOfContents` directive generate heading IDs with predictable     values and       allow for collisions with attacker-controlled `id=toc_N` content (bsc#1271082).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLES16 / SLES_SAP16 host has a package installed that is affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:21858-1 advisory.

    This update for python-mistune fixes the following issues

    - CVE-2026-33079: ReDoS in `LINK_TITLE_RE` can lead to denial of service via a crafted Markdown     (bsc#1264347).
    - CVE-2026-33441: processing of malformed reference links can lead to excessive resource consumption and     denial of       service (bsc#1264752).
    - CVE-2026-44708: improper HTML escaping in the math plugin can lead to XSS (bsc#1264751).
    - CVE-2026-44896: improper escaping in `render_figure` can lead to attribute injection and XSS     (bsc#1264754).
    - CVE-2026-44897: improper sanitization of user-controlled input in `HTMLRenderer.heading` can lead to XSS       (bsc#1264750).
    - CVE-2026-44898: improper sanitization of user-supplied HTML input in `render_toc_ul` can lead to XSS     (bsc#1265052).
    - CVE-2026-44899: improper input verification in Image directive plugin and improper escaping in     `render_block_image`       can lead to CSS injection (bsc#1265053).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote openSUSE 16 host has a package installed that is affected by multiple vulnerabilities as referenced in the openSUSE-SU-2026:20827-1 advisory.

    This update for python-mistune fixes the following issues

    - CVE-2026-33079: ReDoS in `LINK_TITLE_RE` can lead to denial of service via a crafted Markdown     (bsc#1264347).
    - CVE-2026-33441: processing of malformed reference links can lead to excessive resource consumption and     denial of       service (bsc#1264752).
    - CVE-2026-44708: improper HTML escaping in the math plugin can lead to XSS (bsc#1264751).
    - CVE-2026-44896: improper escaping in `render_figure` can lead to attribute injection and XSS     (bsc#1264754).
    - CVE-2026-44897: improper sanitization of user-controlled input in `HTMLRenderer.heading` can lead to XSS       (bsc#1264750).
    - CVE-2026-44898: improper sanitization of user-supplied HTML input in `render_toc_ul` can lead to XSS     (bsc#1265052).
    - CVE-2026-44899: improper input verification in Image directive plugin and improper escaping in     `render_block_image`       can lead to CSS injection (bsc#1265053).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

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

  - Mistune is a Python Markdown parser with renderers and plugins. In 3.2.0 and earlier, in     src/mistune/directives/image.py, the render_figure() function concatenates figclass and figwidth options     directly into HTML attributes without escaping. This allows attribute injection and XSS even when     HTMLRenderer(escape=True) is used, because these values bypass the inline renderer. Version 3.2.1 contains     a patch. (CVE-2026-44896)

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

ID	Name	Product	Family	Type	Severity
465038	Echo: mistune: security update to 3.2.1	Tenable Cloud Security	Echo Local Security Checks	Local	medium
465038	Echo: mistune: security update to 3.2.1	Tenable Self-Hosted Container Security	Echo Local Security Checks	Local	medium
334706	Photon OS 5.0: Python3 PHSA-2026-5.0-92-0947	Nessus	PhotonOS Local Security Checks	Local	medium
327587	SUSE SLES16 Security Update : python-mistune (SUSE-SU-2026:22655-1)	Nessus	SuSE Local Security Checks	Local	medium
327239	openSUSE 16 Security Update : python-mistune (openSUSE-SU-2026:21339-1)	Nessus	SuSE Local Security Checks	Local	medium
318185	SUSE SLES16 Security Update : python-mistune (SUSE-SU-2026:21858-1)	Nessus	SuSE Local Security Checks	Local	high
318089	openSUSE 16 Security Update : python-mistune (openSUSE-SU-2026:20827-1)	Nessus	SuSE Local Security Checks	Local	high
317327	Linux Distros Unpatched Vulnerability : CVE-2026-44896	Nessus	Misc.	Local	medium

Detections

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CVE-2026-44896

medium

Tenable Plugins

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medium

medium

medium

medium

high

high

medium