CVE-2026-86430

league/commonmark versions before 2.9.1 contain multiple denial of service vulnerabilities in fenced code block detection, reference link label lookup, and emphasis delimiter processing that perform super-linear work on crafted input. Attackers can submit specially crafted Markdown with long...

CVE-2026-86431

league/commonmark thephpleague/commonmark versions = 2.7.0 and 2.9.1 contain a cross-site scripting vulnerability in the AttributesExtension. Prefixing an attribute name with a single U+000C form feed byte e.g. \x0Conclick="alert1" bypasses the AttributesHelper::filterAttributes 'on' event-handle...

CVE-2026-86432

commonmark versions from 2.0.0 before 2.8.4 contain a denial of service vulnerability in XmlRenderer that emits depth-proportional indentation for every XML tag. Attackers can provide deeply nested Markdown or AST structures to cause quadratic memory consumption and output amplification, exhausti...

CVE-2026-86433

commonmark versions from 1.5.0 before 2.8.4 contain a denial of service vulnerability in the Attributes extension where AttributesListener::findTargetAndDirection performs quadratic-time sibling list scanning. Unauthenticated attackers can submit approximately 32 KB of repeated attribute blocks t...

UBUNTU-CVE-2026-86431

league/commonmark thephpleague/commonmark versions = 2.7.0 and 2.9.1 contain a cross-site scripting vulnerability in the AttributesExtension. Prefixing an attribute name with a single U+000C form feed byte e.g. \x0Conclick="alert1" bypasses the AttributesHelper::filterAttributes 'on' event-handle...

CVE-2026-86430

league/commonmark versions before 2.9.1 contain multiple denial of service vulnerabilities in fenced code block detection, reference link label lookup, and emphasis delimiter processing that perform super-linear work on crafted input. Attackers can submit specially crafted Markdown with long...

UBUNTU-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...

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...

CVE-2026-86431

league/commonmark thephpleague/commonmark versions = 2.7.0 and 2.9.1 contain a cross-site scripting vulnerability in the AttributesExtension. Prefixing an attribute name with a single U+000C form feed byte e.g. \x0Conclick="alert1" bypasses the AttributesHelper::filterAttributes 'on' event-handle...

CVE-2026-86429

The league/commonmark thephpleague/commonmark library in versions = 1.5.0 and 2.9.1 contains quadratic parsing complexity in its SmartPunctExtension and AttributesExtension. When either extension is explicitly registered on the Environment they are not enabled by default and are excluded from the...

CVE-2026-86432

commonmark versions from 2.0.0 before 2.8.4 contain a denial of service vulnerability in XmlRenderer that emits depth-proportional indentation for every XML tag. Attackers can provide deeply nested Markdown or AST structures to cause quadratic memory consumption and output amplification, exhausti...

UBUNTU-CVE-2026-86430

league/commonmark versions before 2.9.1 contain multiple denial of service vulnerabilities in fenced code block detection, reference link label lookup, and emphasis delimiter processing that perform super-linear work on crafted input. Attackers can submit specially crafted Markdown with long...

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...

UBUNTU-CVE-2026-86432

commonmark versions from 2.0.0 before 2.8.4 contain a denial of service vulnerability in XmlRenderer that emits depth-proportional indentation for every XML tag. Attackers can provide deeply nested Markdown or AST structures to cause quadratic memory consumption and output amplification, exhausti...

UBUNTU-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...

UBUNTU-CVE-2026-86435

commonmark versions from 1.5.0 before 2.8.4 contain a denial of service vulnerability in the Footnote extension that fails to deduplicate footnote definitions. Attackers can craft documents with duplicate footnote definitions and references to create quadratic output expansion, consuming excessiv...

UBUNTU-CVE-2026-86433

commonmark versions from 1.5.0 before 2.8.4 contain a denial of service vulnerability in the Attributes extension where AttributesListener::findTargetAndDirection performs quadratic-time sibling list scanning. Unauthenticated attackers can submit approximately 32 KB of repeated attribute blocks t...

UBUNTU-CVE-2026-86429

The league/commonmark thephpleague/commonmark library in versions = 1.5.0 and 2.9.1 contains quadratic parsing complexity in its SmartPunctExtension and AttributesExtension. When either extension is explicitly registered on the Environment they are not enabled by default and are excluded from the...

CVE-2026-86435

commonmark versions from 1.5.0 before 2.8.4 contain a denial of service vulnerability in the Footnote extension that fails to deduplicate footnote definitions. Attackers can craft documents with duplicate footnote definitions and references to create quadratic output expansion, consuming excessiv...

CVE-2026-86435 commonmark 1.5.0 before 2.8.4 Denial of Service via Footnote

commonmark versions from 1.5.0 before 2.8.4 contain a denial of service vulnerability in the Footnote extension that fails to deduplicate footnote definitions. Attackers can craft documents with duplicate footnote definitions and references to create quadratic output expansion, consuming excessiv...