mistune - Debian Package Tracker

general

source: mistune (main)
version: 3.3.4-1
maintainer: Debian Python Team (DMD)
uploaders: Edward Betts [DMD] – Julien Puydt [DMD]
arch: all
std-ver: 4.7.4
VCS: Git (Browse, QA)

versions [more versions can be listed by madison] [old versions available from snapshot.debian.org]

[pool directory]

o-o-stable: 0.8.4-4
oldstable: 2.0.4-1
stable: 3.1.3-1
testing: 3.1.4-1
unstable: 3.3.4-1

versioned links

0.8.4-4: [.dsc, use dget on this link to retrieve source package] [changelog] [copyright] [rules] [control]
2.0.4-1: [.dsc, use dget on this link to retrieve source package] [changelog] [copyright] [rules] [control]
3.1.3-1: [.dsc, use dget on this link to retrieve source package] [changelog] [copyright] [rules] [control]
3.1.4-1: [.dsc, use dget on this link to retrieve source package] [changelog] [copyright] [rules] [control]
3.3.4-1: [.dsc, use dget on this link to retrieve source package] [changelog] [copyright] [rules] [control]

binaries

python3-mistune

action needed

17 security issues in sid high

There are 17 open security issues in sid.

17 important issues:

CVE-2026-33079: In versions 3.0.0a1 through 3.2.0 of Mistune, there is a ReDoS (Regular Expression Denial of Service) vulnerability in `LINK_TITLE_RE` that allows an attacker who can supply Markdown for parsing to cause denial of service. The regular expression used for parsing link titles contains overlapping alternatives that can trigger catastrophic backtracking. In both the double-quoted and single-quoted branches, a backslash followed by punctuation can be matched either as an escaped punctuation sequence or as two ordinary characters, creating an ambiguous pattern inside a repeated group. If an attacker supplies Markdown containing repeated ! sequences with no closing quote, the regex engine explores an exponential number of backtracking paths. This is reachable through normal Markdown parsing of inline links and block link reference definitions. A small crafted input can therefore cause significant CPU consumption and make applications using Mistune unresponsive.
CVE-2026-44708: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the mistune math plugin renders inline math ($...$) and block math ($$...$$) by concatenating the raw user-supplied content directly into the HTML output without any HTML escaping. This occurs even when the parser is explicitly created with escape=True, which is supposed to guarantee that all user-controlled text is sanitised before reaching the DOM. This vulnerability is fixed in 3.2.1.
CVE-2026-44896: 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-2026-44897: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, HTMLRenderer.heading() builds the opening <hN> tag by string-concatenating the id attribute value directly into the HTML — with no call to escape(), safe_entity(), or any other sanitisation function. A double-quote character " in the id value terminates the attribute, allowing an attacker to inject arbitrary additional attributes (event handlers, src=, href=, etc.) into the heading element. This vulnerability is fixed in 3.2.1.
CVE-2026-44898: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, render_toc_ul() builds a <ul> table-of-contents tree from a list of (level, id, text) tuples. Both the id value (used as href="#<id>") and the text value (used as the visible link label) are inserted into <a> tags via a plain Python format string — with no HTML escaping applied to either value. When heading IDs are derived from user-supplied heading text (the standard use-case for readable slug anchors), an attacker can craft a heading whose text breaks out of the href="#..." attribute context, injecting arbitrary HTML tags including <script> blocks directly into the rendered TOC. This vulnerability is fixed in 3.2.1.
CVE-2026-44899: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the Image directive plugin validates the :width: and :height: options with a regex compiled as _num_re = re.compile(r"^\d+(?:\.\d*)?"). When the validated value is not a plain integer, render_block_image() inserts it directly into a style="width:...;" or style="height:...;" attribute. Because the value was accepted by the prefix-only regex, any CSS after the leading digits reaches the style= attribute verbatim and without escaping. This vulnerability is fixed in 3.2.1.
CVE-2026-49851: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, Mistune is vulnerable to a CPU exhaustion DoS due to superlinear (approximately O(n²)) behavior in parse_link_text. When parsing Markdown containing many consecutive [ characters, parse_link_text repeatedly scans the input using a regex search inside a loop. Each iteration re-scans a large portion of the remaining string, resulting in quadratic-time behavior. An attacker-controlled Markdown input can therefore trigger excessive CPU usage with a very small payload. This vulnerability is fixed in 3.3.0.
CVE-2026-59922: 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 causes quadratic work in src/mistune/plugins/formatting.py when the strikethrough, mark, or insert plugin scans for matching markers from each possible start position, allowing denial of service through CPU exhaustion. This issue is fixed in version 3.3.0.
CVE-2026-59923: Mistune is a Python Markdown parser with renderers and plugins. Prior to 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. This issue is fixed in version 3.3.0.
CVE-2026-59924: 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 that the result remains within the intended markdown directory, allowing crafted include paths to access files outside that directory when markdown files are processed using md.read(). This issue is fixed in version 3.3.0.
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/inline_parser.py because the parser scans forward for matching close markers from every potential opening run, allowing denial of service in default Mistune parsing. This issue is fixed in version 3.3.0.
CVE-2026-59926: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, render_admonition() 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 when HTMLRenderer escape mode is enabled. This issue is fixed in version 3.2.1.
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 RecursionError, and crash the rendering request. This issue is fixed in version 3.3.0.
CVE-2026-59928: 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/block_parser.py and the ref_links environment dictionary handling, allowing denial of service through CPU exhaustion. This issue is fixed in version 3.3.0.
CVE-2026-59929: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the safe_url 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:, and res: to reach rendered href and src attributes and potentially execute script in affected user agents. This issue is fixed in version 3.3.0.
CVE-2026-59930: 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 toc_N values without slugifying the heading text, allowing attacker-controlled id="toc_N" content to collide with generated anchors and redirect same-page navigation, CSS selectors, or JavaScript handlers. This issue is fixed in version 3.3.0.
CVE-2026-76098: Mistune is a Python Markdown parser with renderers and plugins. Versions 3.3.0 through 3.3.2 are vulnerable to DoS through deeply nested tokens. HTML rendering creates deeply nested emphasis tokens from consecutive asterisk characters, and recursive rendering in HTMLRenderer.render_token() can exceed Python's recursion limit and raise RecursionError, allowing crafted Markdown to crash a parsing process. This issue is fixed in version 3.3.3

Created: 2026-05-07 Last update: 2026-09-30 18:00

17 security issues in forky high

There are 17 open security issues in forky.

17 important issues:

CVE-2026-33079: In versions 3.0.0a1 through 3.2.0 of Mistune, there is a ReDoS (Regular Expression Denial of Service) vulnerability in `LINK_TITLE_RE` that allows an attacker who can supply Markdown for parsing to cause denial of service. The regular expression used for parsing link titles contains overlapping alternatives that can trigger catastrophic backtracking. In both the double-quoted and single-quoted branches, a backslash followed by punctuation can be matched either as an escaped punctuation sequence or as two ordinary characters, creating an ambiguous pattern inside a repeated group. If an attacker supplies Markdown containing repeated ! sequences with no closing quote, the regex engine explores an exponential number of backtracking paths. This is reachable through normal Markdown parsing of inline links and block link reference definitions. A small crafted input can therefore cause significant CPU consumption and make applications using Mistune unresponsive.
CVE-2026-44708: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the mistune math plugin renders inline math ($...$) and block math ($$...$$) by concatenating the raw user-supplied content directly into the HTML output without any HTML escaping. This occurs even when the parser is explicitly created with escape=True, which is supposed to guarantee that all user-controlled text is sanitised before reaching the DOM. This vulnerability is fixed in 3.2.1.
CVE-2026-44896: 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-2026-44897: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, HTMLRenderer.heading() builds the opening <hN> tag by string-concatenating the id attribute value directly into the HTML — with no call to escape(), safe_entity(), or any other sanitisation function. A double-quote character " in the id value terminates the attribute, allowing an attacker to inject arbitrary additional attributes (event handlers, src=, href=, etc.) into the heading element. This vulnerability is fixed in 3.2.1.
CVE-2026-44898: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, render_toc_ul() builds a <ul> table-of-contents tree from a list of (level, id, text) tuples. Both the id value (used as href="#<id>") and the text value (used as the visible link label) are inserted into <a> tags via a plain Python format string — with no HTML escaping applied to either value. When heading IDs are derived from user-supplied heading text (the standard use-case for readable slug anchors), an attacker can craft a heading whose text breaks out of the href="#..." attribute context, injecting arbitrary HTML tags including <script> blocks directly into the rendered TOC. This vulnerability is fixed in 3.2.1.
CVE-2026-44899: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the Image directive plugin validates the :width: and :height: options with a regex compiled as _num_re = re.compile(r"^\d+(?:\.\d*)?"). When the validated value is not a plain integer, render_block_image() inserts it directly into a style="width:...;" or style="height:...;" attribute. Because the value was accepted by the prefix-only regex, any CSS after the leading digits reaches the style= attribute verbatim and without escaping. This vulnerability is fixed in 3.2.1.
CVE-2026-49851: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, Mistune is vulnerable to a CPU exhaustion DoS due to superlinear (approximately O(n²)) behavior in parse_link_text. When parsing Markdown containing many consecutive [ characters, parse_link_text repeatedly scans the input using a regex search inside a loop. Each iteration re-scans a large portion of the remaining string, resulting in quadratic-time behavior. An attacker-controlled Markdown input can therefore trigger excessive CPU usage with a very small payload. This vulnerability is fixed in 3.3.0.
CVE-2026-59922: 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 causes quadratic work in src/mistune/plugins/formatting.py when the strikethrough, mark, or insert plugin scans for matching markers from each possible start position, allowing denial of service through CPU exhaustion. This issue is fixed in version 3.3.0.
CVE-2026-59923: Mistune is a Python Markdown parser with renderers and plugins. Prior to 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. This issue is fixed in version 3.3.0.
CVE-2026-59924: 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 that the result remains within the intended markdown directory, allowing crafted include paths to access files outside that directory when markdown files are processed using md.read(). This issue is fixed in version 3.3.0.
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/inline_parser.py because the parser scans forward for matching close markers from every potential opening run, allowing denial of service in default Mistune parsing. This issue is fixed in version 3.3.0.
CVE-2026-59926: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, render_admonition() 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 when HTMLRenderer escape mode is enabled. This issue is fixed in version 3.2.1.
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 RecursionError, and crash the rendering request. This issue is fixed in version 3.3.0.
CVE-2026-59928: 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/block_parser.py and the ref_links environment dictionary handling, allowing denial of service through CPU exhaustion. This issue is fixed in version 3.3.0.
CVE-2026-59929: Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the safe_url 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:, and res: to reach rendered href and src attributes and potentially execute script in affected user agents. This issue is fixed in version 3.3.0.
CVE-2026-59930: 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 toc_N values without slugifying the heading text, allowing attacker-controlled id="toc_N" content to collide with generated anchors and redirect same-page navigation, CSS selectors, or JavaScript handlers. This issue is fixed in version 3.3.0.
CVE-2026-76098: Mistune is a Python Markdown parser with renderers and plugins. Versions 3.3.0 through 3.3.2 are vulnerable to DoS through deeply nested tokens. HTML rendering creates deeply nested emphasis tokens from consecutive asterisk characters, and recursive rendering in HTMLRenderer.render_token() can exceed Python's recursion limit and raise RecursionError, allowing crafted Markdown to crash a parsing process. This issue is fixed in version 3.3.3

Created: 2026-05-07 Last update: 2026-09-30 18:00

Failed to analyze the VCS repository. Please troubleshoot and fix the issue. high

vcswatch reports that there is an error with this package's VCS, or the debian/changelog file inside it. Please check the error shown below and try to fix it. You might have to update the VCS URL in the debian/control file to point to the correct repository.

Auto packing the repository in background for optimum performance. See 'git help gc' for manual housekeeping. fatal: shallow file has changed since we read it

Created: 2026-09-30 Last update: 2026-09-30 15:31

9 security issues in bullseye high

There are 9 open security issues in bullseye.

1 important issue:

CVE-2026-76098: Mistune is a Python Markdown parser with renderers and plugins. Versions 3.3.0 through 3.3.2 are vulnerable to DoS through deeply nested tokens. HTML rendering creates deeply nested emphasis tokens from consecutive asterisk characters, and recursive rendering in HTMLRenderer.render_token() can exceed Python's recursion limit and raise RecursionError, allowing crafted Markdown to crash a parsing process. This issue is fixed in version 3.3.3

8 issues postponed or untriaged:

CVE-2022-34749: (needs triaging) In mistune through 2.0.2, support of inline markup is implemented by using regular expressions that can involve a high amount of backtracking on certain edge cases. This behavior is commonly named catastrophic backtracking.
CVE-2026-44708: (needs triaging) Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the mistune math plugin renders inline math ($...$) and block math ($$...$$) by concatenating the raw user-supplied content directly into the HTML output without any HTML escaping. This occurs even when the parser is explicitly created with escape=True, which is supposed to guarantee that all user-controlled text is sanitised before reaching the DOM. This vulnerability is fixed in 3.2.1.
CVE-2026-44896: (needs triaging) 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-2026-44897: (needs triaging) Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, HTMLRenderer.heading() builds the opening <hN> tag by string-concatenating the id attribute value directly into the HTML — with no call to escape(), safe_entity(), or any other sanitisation function. A double-quote character " in the id value terminates the attribute, allowing an attacker to inject arbitrary additional attributes (event handlers, src=, href=, etc.) into the heading element. This vulnerability is fixed in 3.2.1.
CVE-2026-44898: (needs triaging) Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, render_toc_ul() builds a <ul> table-of-contents tree from a list of (level, id, text) tuples. Both the id value (used as href="#<id>") and the text value (used as the visible link label) are inserted into <a> tags via a plain Python format string — with no HTML escaping applied to either value. When heading IDs are derived from user-supplied heading text (the standard use-case for readable slug anchors), an attacker can craft a heading whose text breaks out of the href="#..." attribute context, injecting arbitrary HTML tags including <script> blocks directly into the rendered TOC. This vulnerability is fixed in 3.2.1.
CVE-2026-44899: (needs triaging) Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the Image directive plugin validates the :width: and :height: options with a regex compiled as _num_re = re.compile(r"^\d+(?:\.\d*)?"). When the validated value is not a plain integer, render_block_image() inserts it directly into a style="width:...;" or style="height:...;" attribute. Because the value was accepted by the prefix-only regex, any CSS after the leading digits reaches the style= attribute verbatim and without escaping. This vulnerability is fixed in 3.2.1.
CVE-2026-59923: (postponed; to be fixed through a stable update) Mistune is a Python Markdown parser with renderers and plugins. Prior to 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. This issue is fixed in version 3.3.0.
CVE-2026-59929: (postponed; to be fixed through a stable update) Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the safe_url 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:, and res: to reach rendered href and src attributes and potentially execute script in affected user agents. This issue is fixed in version 3.3.0.

Created: 2026-08-25 Last update: 2026-08-27 21:31

lintian reports 1 warning normal

Lintian reports 1 warning about this package. You should make the package lintian clean getting rid of them.

Created: 2026-09-30 Last update: 2026-09-30 21:00

17 low-priority security issues in trixie low

There are 17 open security issues in trixie.

17 issues left for the package maintainer to handle:

CVE-2026-33079: (postponed; to be fixed through a stable update) In versions 3.0.0a1 through 3.2.0 of Mistune, there is a ReDoS (Regular Expression Denial of Service) vulnerability in `LINK_TITLE_RE` that allows an attacker who can supply Markdown for parsing to cause denial of service. The regular expression used for parsing link titles contains overlapping alternatives that can trigger catastrophic backtracking. In both the double-quoted and single-quoted branches, a backslash followed by punctuation can be matched either as an escaped punctuation sequence or as two ordinary characters, creating an ambiguous pattern inside a repeated group. If an attacker supplies Markdown containing repeated ! sequences with no closing quote, the regex engine explores an exponential number of backtracking paths. This is reachable through normal Markdown parsing of inline links and block link reference definitions. A small crafted input can therefore cause significant CPU consumption and make applications using Mistune unresponsive.
CVE-2026-44708: (needs triaging) Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the mistune math plugin renders inline math ($...$) and block math ($$...$$) by concatenating the raw user-supplied content directly into the HTML output without any HTML escaping. This occurs even when the parser is explicitly created with escape=True, which is supposed to guarantee that all user-controlled text is sanitised before reaching the DOM. This vulnerability is fixed in 3.2.1.
CVE-2026-44896: (needs triaging) 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-2026-44897: (needs triaging) Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, HTMLRenderer.heading() builds the opening <hN> tag by string-concatenating the id attribute value directly into the HTML — with no call to escape(), safe_entity(), or any other sanitisation function. A double-quote character " in the id value terminates the attribute, allowing an attacker to inject arbitrary additional attributes (event handlers, src=, href=, etc.) into the heading element. This vulnerability is fixed in 3.2.1.
CVE-2026-44898: (needs triaging) Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, render_toc_ul() builds a <ul> table-of-contents tree from a list of (level, id, text) tuples. Both the id value (used as href="#<id>") and the text value (used as the visible link label) are inserted into <a> tags via a plain Python format string — with no HTML escaping applied to either value. When heading IDs are derived from user-supplied heading text (the standard use-case for readable slug anchors), an attacker can craft a heading whose text breaks out of the href="#..." attribute context, injecting arbitrary HTML tags including <script> blocks directly into the rendered TOC. This vulnerability is fixed in 3.2.1.
CVE-2026-44899: (needs triaging) Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the Image directive plugin validates the :width: and :height: options with a regex compiled as _num_re = re.compile(r"^\d+(?:\.\d*)?"). When the validated value is not a plain integer, render_block_image() inserts it directly into a style="width:...;" or style="height:...;" attribute. Because the value was accepted by the prefix-only regex, any CSS after the leading digits reaches the style= attribute verbatim and without escaping. This vulnerability is fixed in 3.2.1.
CVE-2026-49851: (needs triaging) Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, Mistune is vulnerable to a CPU exhaustion DoS due to superlinear (approximately O(n²)) behavior in parse_link_text. When parsing Markdown containing many consecutive [ characters, parse_link_text repeatedly scans the input using a regex search inside a loop. Each iteration re-scans a large portion of the remaining string, resulting in quadratic-time behavior. An attacker-controlled Markdown input can therefore trigger excessive CPU usage with a very small payload. This vulnerability is fixed in 3.3.0.
CVE-2026-59922: (needs triaging) 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 causes quadratic work in src/mistune/plugins/formatting.py when the strikethrough, mark, or insert plugin scans for matching markers from each possible start position, allowing denial of service through CPU exhaustion. This issue is fixed in version 3.3.0.
CVE-2026-59923: (needs triaging) Mistune is a Python Markdown parser with renderers and plugins. Prior to 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. This issue is fixed in version 3.3.0.
CVE-2026-59924: (needs triaging) 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 that the result remains within the intended markdown directory, allowing crafted include paths to access files outside that directory when markdown files are processed using md.read(). This issue is fixed in version 3.3.0.
CVE-2026-59925: (needs triaging) 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/inline_parser.py because the parser scans forward for matching close markers from every potential opening run, allowing denial of service in default Mistune parsing. This issue is fixed in version 3.3.0.
CVE-2026-59926: (needs triaging) Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, render_admonition() 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 when HTMLRenderer escape mode is enabled. This issue is fixed in version 3.2.1.
CVE-2026-59927: (needs triaging) 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 RecursionError, and crash the rendering request. This issue is fixed in version 3.3.0.
CVE-2026-59928: (needs triaging) 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/block_parser.py and the ref_links environment dictionary handling, allowing denial of service through CPU exhaustion. This issue is fixed in version 3.3.0.
CVE-2026-59929: (needs triaging) Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the safe_url 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:, and res: to reach rendered href and src attributes and potentially execute script in affected user agents. This issue is fixed in version 3.3.0.
CVE-2026-59930: (needs triaging) 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 toc_N values without slugifying the heading text, allowing attacker-controlled id="toc_N" content to collide with generated anchors and redirect same-page navigation, CSS selectors, or JavaScript handlers. This issue is fixed in version 3.3.0.
CVE-2026-76098: (needs triaging) Mistune is a Python Markdown parser with renderers and plugins. Versions 3.3.0 through 3.3.2 are vulnerable to DoS through deeply nested tokens. HTML rendering creates deeply nested emphasis tokens from consecutive asterisk characters, and recursive rendering in HTMLRenderer.render_token() can exceed Python's recursion limit and raise RecursionError, allowing crafted Markdown to crash a parsing process. This issue is fixed in version 3.3.3

You can find information about how to handle these issues in the security team's documentation.

Created: 2026-05-07 Last update: 2026-09-30 18:00

testing migrations

excuses:
- Migration status for mistune (3.1.4-1 to 3.3.4-1): BLOCKED: Rejected/violates migration policy/introduces a regression
- Issues preventing migration:
- ∙ ∙ Autopkgtest for giara/1.1.0-0.1: amd64: No tests, superficial or marked flaky ♻, arm64: No tests, superficial or marked flaky ♻, armhf: No tests, superficial or marked flaky ♻, i386: No tests, superficial or marked flaky ♻, ppc64el: No tests, superficial or marked flaky ♻, riscv64: No tests, superficial or marked flaky ♻ (reference ♻), s390x: Test triggered
- ∙ ∙ Autopkgtest for hyperkitty/1.3.12-7: amd64: Regression ♻ (reference ♻), arm64: Regression ♻ (reference ♻), armhf: Regression ♻ (reference ♻), i386: Reference test triggered, but real test failed already ♻, ppc64el: Regression ♻ (reference ♻), riscv64: Regression ♻ (reference ♻), s390x: Test triggered
- ∙ ∙ Autopkgtest for iredis/1.16.1-3: amd64: No tests, superficial or marked flaky ♻, arm64: No tests, superficial or marked flaky ♻, armhf: No tests, superficial or marked flaky ♻, i386: No tests, superficial or marked flaky ♻, ppc64el: No tests, superficial or marked flaky ♻, riscv64: No tests, superficial or marked flaky ♻ (reference ♻), s390x: Test triggered
- ∙ ∙ Autopkgtest for markdown-it-py/4.2.0-4: amd64: Pass, arm64: Pass, armhf: Pass, i386: Pass, ppc64el: Pass, riscv64: Pass, s390x: Test triggered
- ∙ ∙ Autopkgtest for mistune/3.3.4-1: amd64: Pass, arm64: Pass, armhf: Pass, i386: Pass, ppc64el: Pass, riscv64: Pass, s390x: Test triggered
- ∙ ∙ Autopkgtest for nbconvert/7.17.1-2: amd64: Pass, arm64: Pass, armhf: Pass, i386: Pass, ppc64el: Pass, riscv64: Pass, s390x: Test triggered
- ∙ ∙ Autopkgtest for pyinstaller-hooks-contrib/2026.7-1: amd64: Pass, arm64: Pass, armhf: Pass, i386: Pass, ppc64el: Failed (not a regression) ♻ (reference ♻), riscv64: Failed (not a regression) ♻ (reference ♻), s390x: Test triggered
- ∙ ∙ Autopkgtest for python-flasgger/0.9.7.2~dev2+dfsg-4: amd64: Pass, arm64: Pass, armhf: Pass, i386: Pass, ppc64el: Pass, riscv64: Pass, s390x: Test triggered
- ∙ ∙ Autopkgtest for python-m2r2: s390x: Test triggered
- ∙ ∙ Autopkgtest for python-schema-salad/8.9.20260417192335-2: amd64: Pass, arm64: Pass, armhf: Pass, i386: Pass, ppc64el: Pass, riscv64: Pass, s390x: Test triggered
- ∙ ∙ Autopkgtest for sphinx-mdinclude/0.6.2-2: amd64: Pass, arm64: Pass, armhf: Pass, i386: Pass, ppc64el: Pass, riscv64: Pass, s390x: Test triggered
- ∙ ∙ Too young, only 3 of 5 days old
- Additional info (not blocking):
- ∙ ∙ Piuparts tested OK - https://piuparts.debian.org/sid/source/m/mistune.html
- ∙ ∙ Reproduced on amd64 - info
- ∙ ∙ Reproduced on arm64 - info
- ∙ ∙ Reproduced on armhf - info
- ∙ ∙ Reproduced on i386 - info
- Not considered

news

[rss feed]

[2026-09-30] Accepted mistune 3.3.4-1 (source) into unstable (Edward Betts)
[2025-09-11] mistune 3.1.4-1 MIGRATED to testing (Debian testing watch)
[2025-09-09] Accepted mistune 3.1.4-1 (source) into unstable (Colin Watson)
[2025-04-27] mistune 3.1.3-1 MIGRATED to testing (Debian testing watch)
[2025-03-31] Accepted mistune 3.1.3-1 (source) into unstable (Boyuan Yang)
[2024-10-14] mistune 3.0.2-2 MIGRATED to testing (Debian testing watch)
[2024-10-11] Accepted mistune 3.0.2-2 (source) into unstable (Boyuan Yang)
[2024-01-20] mistune 3.0.2-1 MIGRATED to testing (Debian testing watch)
[2023-12-12] Accepted mistune 3.0.2-1 (source) into unstable (Julien Puydt)
[2023-07-17] mistune 2.0.4-2 MIGRATED to testing (Debian testing watch)
[2023-07-13] Accepted mistune 2.0.4-2 (source) into unstable (Bastian Germann) (signed by: bage@debian.org)
[2022-07-21] mistune 2.0.4-1 MIGRATED to testing (Debian testing watch)
[2022-07-19] Accepted mistune 2.0.4-1 (source) into unstable (Julien Puydt)
[2022-07-13] mistune 2.0.3-1 MIGRATED to testing (Debian testing watch)
[2022-07-13] mistune 2.0.3-1 MIGRATED to testing (Debian testing watch)
[2022-07-10] Accepted mistune 2.0.3-1 (source) into unstable (Julien Puydt)
[2022-04-14] mistune 2.0.2-1 MIGRATED to testing (Debian testing watch)
[2022-03-31] Accepted mistune 2.0.2-1 (source) into unstable (Pierre-Elliott Bécue)
[2022-03-31] Accepted mistune 2.0.0.0+really2.0.0-1 (source) into unstable (Pierre-Elliott Bécue)
[2022-01-20] mistune 2.0.0-1+really0.8.4-1 MIGRATED to testing (Debian testing watch)
[2022-01-12] Accepted mistune 2.0.0.0+really2.0.0-1~exp1 (source) into experimental (Pierre-Elliott Bécue)
[2022-01-11] Accepted mistune 2.0.0-1+really0.8.4-1 (source) into unstable (Pierre-Elliott Bécue)
[2021-12-05] Accepted mistune 2.0.0-1 (source) into unstable (Pierre-Elliott Bécue)
[2021-11-29] Accepted mistune 2.0.0~rc1-1~exp1 (source) into experimental (Pierre-Elliott Bécue)
[2021-08-27] mistune 0.8.4-5 MIGRATED to testing (Debian testing watch)
[2021-08-25] Accepted mistune 0.8.4-5 (source) into unstable (Sandro Tosi)
[2020-10-15] mistune 0.8.4-4 MIGRATED to testing (Debian testing watch)
[2020-10-12] Accepted mistune 0.8.4-4 (source) into unstable (Julien Puydt)
[2020-07-11] mistune 0.8.4-3 MIGRATED to testing (Debian testing watch)
[2020-07-08] Accepted mistune 0.8.4-3 (source) into unstable (Julien Puydt)

bugs [bug history graph]

all: 4
RC: 0
I&N: 4
M&W: 0
F&P: 0
patch: 0

links

homepage
lintian (0, 1)
buildd: logs, reproducibility
popcon
browse source code
other distros
security tracker
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ubuntu

[Information about Ubuntu for Debian Developers]

version: 3.1.4-1