Threats affecting pkg:pypi/mistune

Mistune before 3.3.3 contains a denial of service vulnerability in InlineParser.parse_link that allows attackers to cause quadratic CPU growth by supplying balanced nested brackets. Attackers can submit crafted Markdown with thousands of nested bracket pairs not forming a valid link, triggering repeated _contains_nested_link scans that exhaust CPU in parsing applications.

Mistune from 3.3.0 before 3.3.4 contains a denial of service vulnerability that allows remote attackers to exhaust CPU through quadratic-time emphasis delimiter processing. Attackers can submit small markdown documents with repeated patterns like "*a_b" to trigger an O(n²) index-fixup loop, stalling workers for seconds.

Mistune versions prior to 3.3.0 contain a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by using '../' sequences in include paths. Additionally, attackers can inject HTML through unescaped error messages and included file contents, enabling cross-site scripting (XSS) even when escape=True is set. This vulnerability is fixed in version 3.3.0.

Mistune versions before 3.3.0 have a path traversal vulnerability in the opt-in Include directive. This flaw allows attackers to read arbitrary local files by providing relative or absolute paths. Exploitation can lead to disclosure of sensitive files such as /etc/passwd and injection of unescaped HTML or script content into rendered Markdown output.

Mistune versions prior to 3.3.0 contain a critical path traversal vulnerability in the RST include directive. This flaw allows attackers to read arbitrary files on the system by using relative or absolute paths in markdown include directives. Sensitive files such as credentials or environment data can be exposed in rendered HTML output. The vulnerability is fixed in version 3.3.0.

Mistune versions prior to 3.3.0 contain an algorithmic complexity vulnerability in the inline link parser. This flaw allows unauthenticated attackers to exhaust CPU resources by submitting markdown inputs with long sequences of unmatched '[' characters. The vulnerability causes the parser to perform O(N^2) operations, leading to significant delays in rendering, with 16 KB inputs potentially occupying workers for over 30 seconds. A fix is available in version 3.3.0.

Mistune versions from 3.2.1 up to but not including 3.3.0 have a CSS injection vulnerability via the unvalidated figwidth option in the figure directive. This flaw allows attackers controlling markdown input to inject arbitrary CSS style declarations, such as background:url(), which can cause victim browsers to send requests to attacker-controlled servers and potentially leak attribute values. The vulnerability is fixed in version 3.3.0.

Mistune versions before 3.3.0 contain a cross-site scripting (XSS) vulnerability in the Include directive. This flaw allows attackers who can place an HTML file readable by the renderer to execute stored scripts by referencing the file via an include directive combined with path traversal, when escape=False is set. The vulnerability is fixed in version 3.3.0.

Mistune versions 3.0.0 up to but not including 3.3.0 contain a denial of service vulnerability due to inefficient regular expression complexity in the parse_link_text function. This flaw allows attackers to craft markdown input with deeply nested square brackets that cause quadratic parsing time, leading to excessive CPU consumption. The issue is fixed in version 3.3.0.

Mistune versions from 3.0.0 up to but not including 3.3.0 have an algorithmic complexity vulnerability in the inline link parser. This flaw allows unauthenticated attackers to cause excessive CPU consumption by submitting Markdown with many unbalanced '[' or '![' characters, leading to repeated unbounded scans and tying up worker processes for minutes. The vulnerability is fixed in version 3.3.0.

Mistune versions prior to 3.3.0 contain an inefficient algorithmic complexity vulnerability in the parse_link_text function. This flaw allows remote attackers to cause a denial of service by submitting markdown with long runs of unmatched square brackets. The vulnerability triggers repeated forward scans in mistune.html(), stalling worker processes for extended periods.

Mistune versions 3.3.0 through 3.3.2 contain a denial-of-service vulnerability caused by uncontrolled recursion during HTML rendering of deeply nested emphasis tokens. This can trigger a Python RecursionError and crash the parsing process. The issue is resolved in version 3.3.3.

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.

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.

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.

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.

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.

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.

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.