CVE-2026-86434

league/commonmark versions = 2.0.0 and 2.8.4 patched in 2.9.0 contain a denial of service vulnerability in UniqueSlugNormalizer::normalize, which restarts its numeric-suffix search from 1 on every slug collision, resulting in OK^2 time complexity for K headings that collapse to the same base slug...

DEBIAN-CVE-2026-86428

commonmark versions from 1.5.0 before 2.10.0 contain a denial of service vulnerability in the AttributesExtension when processing distinctly-named attributes. Attackers can submit Markdown with numerous distinct attribute names to cause quadratic-time attribute merging and filtering, consuming...

CVE-2026-20841

CVE-2026-20841 - Windows 记事本远程代码执行 RCE 安全研究与技术分析仓库 ⚠️ 本仓库仅供教育、防御和研究目的使用。 📖 概述 CVE-2026-20841 是一个影响 Microsoft Windows 记事本 Markdown 处理功能的严重远程代码执行 RCE 漏洞。 当受影响的 Windows 记事本版本打开特制文件时，攻击者可能触发任意代码执行。 影响 远程代码执行 RCE 任意代码执行 可能用户级妥协 安全边界绕过 恶意软件投递向量 🎯 受影响产品 产品| 状态 ---|--- Windows 11 记事本| 受影响 Windows 10 记事本|...

Linux Distros Unpatched Vulnerability : CVE-2026-86431

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - league/commonmark thephpleague/commonmark versions = 2.7.0 and 2.9.1 contain a cross-site scripting vulnerability in the AttributesExtension. Prefixing an...

Linux Distros Unpatched Vulnerability : CVE-2026-86434

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - league/commonmark versions = 2.0.0 and 2.8.4 patched in 2.9.0 contain a denial of service vulnerability in UniqueSlugNormalizer::normalize, which restarts its...

CVE-2026-53758 Emlog: Stored XSS via Parsedown Markdown Processing - Raw HTML Not Sanitized

Emlog is an open source website building system. In versions 2.6.29 and prior, article content is processed by Parsedown without enabling safe mode, which means raw HTML including tags embedded in Markdown is passed through unescaped. The output is rendered with no additional sanitization,...

CVE-2026-80180

Stored XSS via markdown HTML processing in Apache Allura. This issue affects Apache Allura: from through 1.20.0. Users are recommended to upgrade to version 1.21.0, which fixes the issue...

EUVD-2026-70921

Stored XSS via markdown HTML processing in Apache Allura. This issue affects Apache Allura: from through 1.20.0. Users are recommended to upgrade to version 1.21.0, which fixes the issue...

CVE-2026-80180 Apache Allura: Stored XSS via markdown HTML processing

Stored XSS via markdown HTML processing in Apache Allura. This issue affects Apache Allura: from through 1.20.0. Users are recommended to upgrade to version 1.21.0, which fixes the issue...

CVE-2026-80180

Apache Allura versions through 1.20.0 are affected by a stored cross-site scripting (XSS) vulnerability in its markdown HTML processing pipeline. An attacker can inject malicious HTML that executes in other users' browsers upon viewing the content. The CVSS 3.1 score is 6.1 (MEDIUM) with a vector...

linkify-it: linkify-it: Denial of Service via algorithmic complexity vulnerability

A flaw was found in linkify-it, a library for recognizing links with full Unicode support. The LinkifyIt.prototype.match function, the package's primary public API, has an algorithmic complexity of ON² for inputs containing many fuzzy links or emails. This can be exploited by a remote attacker...

GHSA-R4RV-85JG-W4MF Mistune: Arbitrary File Read via Include directive path traversal

Summary A path traversal issue exists in mistune's Include directive when markdown files are processed using md.read. A crafted include path can cause files outside the intended markdown directory to be accessed. Details The issue occurs in the Include.parse method where user-supplied paths are...

PT-2026-56517

Name of the Vulnerable Software and Affected Versions Mistune versions prior to 3.3.0 Description Mistune is a Python Markdown parser with renderers and plugins. The Include.parse function joins and normalizes user-supplied include paths without verifying that the result remains within the intend...

OSV-2026-816 Heap-buffer-overflow in md_process_all_blocks

OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=516422428 Crash type: Heap-buffer-overflow READ Crash state: mdprocessallblocks mdparse mdhtml...

PT-2026-47121

OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=516422428 Crash type: Heap-buffer-overflow READ Crash state: md process all blocks md parse md html...

Sveltia CMS: Stored XSS in entry summary rendering via entity-decoded HTML

Impact A stored cross-site scripting XSS vulnerability affected entry summary rendering in Sveltia CMS. Entry summaries that allowed limited Markdown were parsed, sanitized, and then HTML entities were decoded. This order allowed specially crafted entity-encoded HTML, such as encoded tags or even...

GHSA-97R8-RF7Q-WMJW Sveltia CMS: Stored XSS in entry summary rendering via entity-decoded HTML

Impact A stored cross-site scripting XSS vulnerability affected entry summary rendering in Sveltia CMS. Entry summaries that allowed limited Markdown were parsed, sanitized, and then HTML entities were decoded. This order allowed specially crafted entity-encoded HTML, such as encoded tags or even...

Cross-site Scripting (XSS)

Overview getgrav/grav is a Modern, Crazy Fast, Ridiculously Easy and Amazingly Powerful Flat-File CMS. Affected versions of this package are vulnerable to Cross-site Scripting XSS in the attribute process. An attacker can execute arbitrary JavaScript in the context of users who view a page by...

CVE-2026-1090

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 10.6 before 18.7.6, 18.8 before 18.8.6, and 18.9 before 18.9.2 that could have allowed an authenticated user, when the markdownplaceholders feature flag was enabled, to inject JavaScript in a browser due to improper...

EUVD-2026-11180

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 10.6 before 18.7.6, 18.8 before 18.8.6, and 18.9 before 18.9.2 that could have allowed an authenticated user, when the markdownplaceholders feature flag was enabled, to inject JavaScript in a browser due to improper...