CVE-2026-59929

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:, vbscript:, file:, and data: schemes, allowing legacy or chained schemes such as feed:, view-source:, jar:, livescript:, mocha:, ms-its:, mk:...

CVE-2026-59929 Mistune renderers/html.safe_url: HARMFUL_PROTOCOLS list misses legacy and chained schemes that historically chain to `javascript:` execution

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:, vbscript:, file:, and data: schemes, allowing legacy or chained schemes such as feed:, view-source:, jar:, livescript:, mocha:, ms-its:, mk:...

CVE-2026-59925 inline_parser: quadratic-time parsing on long runs of `**x**` and `***x***` emphasis pairs

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 around a character cause quadratic work in src/mistune/inlineparser.py because the parser scans forward for matching close markers from...

CVE-2026-59925 inline_parser: quadratic-time parsing on long runs of `**x**` and `***x***` emphasis pairs

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 around a character cause quadratic work in src/mistune/inlineparser.py because the parser scans forward for matching close markers from...

CVE-2026-59925

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 around a character cause quadratic work in src/mistune/inlineparser.py because the parser scans forward for matching close markers from...

CVE-2026-59925

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 around a character cause quadratic work in src/mistune/inlineparser.py because the parser scans forward for matching close markers from...

CVE-2026-59925 inline_parser: quadratic-time parsing on long runs of `**x**` and `***x***` emphasis pairs

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 around a character cause quadratic work in src/mistune/inlineparser.py because the parser scans forward for matching close markers from...

CVE-2026-59925

The CVE-2026-59925 affects Mistune, a Python Markdown parser. Before version 3.3.0, long sequences of well-formed emphasis markers (/x / or /x * around a character) trigger quadratic work in src/mistune/inline_parser.py by scanning for matching close markers from each opening run, enabling denial...

CVE-2026-59926

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-2026-59926 Mistune: XSS via unescaped class option in Admonition directive

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-2026-59926 Mistune: XSS via unescaped class option in Admonition directive

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-2026-59926

CVE-2026-59926 : Mistune (Python Markdown parser) contains an XSS due to render_admonition() in src/mistune/directives/admonition.py failing to escape the Admonition directive :class: option when constructing the HTML class attribute. This allows attribute injection and cross-site scripting even ...

CVE-2026-59926

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-2026-59926 Mistune: XSS via unescaped class option in Admonition directive

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-2026-59923 Mistune: XSS via percent-encoded javascript URI bypass in safe_url()

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 attacker-supplied Markdown links or images to bypass URL protections and execute script in rendered HTML. This issue is fixed in version...

CVE-2026-59923 Mistune: XSS via percent-encoded javascript URI bypass in safe_url()

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 attacker-supplied Markdown links or images to bypass URL protections and execute script in rendered HTML. This issue is fixed in version...

CVE-2026-59923

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 attacker-supplied Markdown links or images to bypass URL protections and execute script in rendered HTML. This issue is fixed in version...

CVE-2026-59923

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 attacker-supplied Markdown links or images to bypass URL protections and execute script in rendered HTML. This issue is fixed in version...

CVE-2026-59923

CVE-2026-59923 affects Mistune, a Python Markdown parser. Before 3.3.0, HTMLRenderer.safe_url() does not block percent-encoded javascript URIs, allowing attacker-supplied Markdown links or images to bypass URL protections and execute script in rendered HTML. The issue is fixed in version 3.3.0. E...

CVE-2026-59923 Mistune: XSS via percent-encoded javascript URI bypass in safe_url()

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 attacker-supplied Markdown links or images to bypass URL protections and execute script in rendered HTML. This issue is fixed in version...