CVE-2026-59925

A flaw was found in Mistune, a Python Markdown parser. An attacker can exploit this vulnerability by providing specially crafted Markdown input containing long sequences of emphasis pairs. This can cause the parser to perform excessive computational work, leading to a denial of service DoS...

CVE-2026-59928

A flaw was found in Mistune, a Python Markdown parser. A remote attacker could exploit this vulnerability by providing a specially crafted Markdown document containing numerous repeated or distinct reference-link definitions. This can lead to excessive processing, causing CPU exhaustion and a...

CVE-2026-59927

A flaw was found in Mistune, a Python Markdown parser. The Include directive in Mistune's src/mistune/directives/include.py does not properly detect indirect cycles when two Markdown files include each other. This oversight allows for unbounded recursion, which can lead to a RecursionError and...

Linux Distros Unpatched Vulnerability : CVE-2026-59924

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. Prior to 3.3.0, Include.parse joins and normalizes user-supplied include paths without verifying...

Linux Distros Unpatched Vulnerability : CVE-2026-59926

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. Prior to 3.2.1, renderadmonition in src/mistune/directives/admonition.py concatenates the...

Linux Distros Unpatched Vulnerability : CVE-2026-59927

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. Prior to 3.3.0, the Include directive in src/mistune/directives/include.py detects only direct...

Linux Distros Unpatched Vulnerability : CVE-2026-59930

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. Prior to 3.3.0, the toc plugin and TableOfContents directive generate heading IDs as predictable...

Linux Distros Unpatched Vulnerability : CVE-2026-59929

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. Prior to 3.3.0, the safeurl filter in src/mistune/renderers/html.py blocks only javascript:,...

Linux Distros Unpatched Vulnerability : CVE-2026-59922

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. Prior to 3.3.0, a run of closed tilde, equals-sign, or caret marker pairs around a character...

Linux Distros Unpatched Vulnerability : CVE-2026-59928

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. Prior to 3.3.0, a Markdown document containing many repeated or distinct reference-link...

Linux Distros Unpatched Vulnerability : CVE-2026-59925

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. Prior to 3.3.0, long sequences of well- formed double-asterisk or triple-asterisk emphasis pairs...

Linux Distros Unpatched Vulnerability : CVE-2026-59923

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. Prior to 3.3.0, HTMLRenderer.safeurl does not block percent-encoded javascript URIs, allowing...

Inefficient Algorithmic Complexity

Overview Affected versions of this package are vulnerable to Inefficient Algorithmic Complexity through the parsing process in formatting.py when handling long sequences of , ==, or ^^ markers. An attacker can cause excessive CPU consumption by submitting specially crafted input containing long...

Insufficient Verification of Data Authenticity

Overview Affected versions of this package are vulnerable to Insufficient Verification of Data Authenticity via the toc process. An attacker can interfere with same-page navigation, CSS selectors, or JavaScript handlers by creating content with predictable id attributes that collide with...

Inefficient Algorithmic Complexity

Overview Affected versions of this package are vulnerable to Inefficient Algorithmic Complexity in the inlineparser process. An attacker can cause excessive resource consumption by submitting input containing long sequences of double-asterisk or triple-asterisk emphasis pairs, leading to...

Inefficient Algorithmic Complexity

Overview Affected versions of this package are vulnerable to Inefficient Algorithmic Complexity via the blockparser process. An attacker can cause excessive CPU consumption by submitting specially crafted Markdown documents containing numerous repeated or distinct reference-link definitions...

Uncontrolled Recursion

Overview Affected versions of this package are vulnerable to Uncontrolled Recursion through the include process. An attacker can cause the application to crash by creating two markdown files that recursively include each other, leading to unbounded recursion and a RecursionError. Remediation...

PYSEC-2026-2214

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, renderadmonition in src/mistune/directives/admonition.py concatenates the Admonition directive :class: option into the HTML class attribute without escaping, allowing attribute injection and cross-site scripting even...

CVE-2026-59927

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the Include directive in src/mistune/directives/include.py detects only direct self-includes and not indirect cycles, allowing two markdown files that include each other to trigger unbounded recursion, raise...

PYSEC-2026-2216

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, a Markdown document containing many repeated or distinct reference-link definitions causes quadratic work in src/mistune/blockparser.py and the reflinks environment dictionary handling, allowing denial of service...