Pydantic AI: Excessive resource use when local web fetching converts nested HTML

SummaryApplications using Pydantic AI's local web-fetch tool can experience excessive CPU and memory use when it converts attacker-controlled HTML. An agent must fetch the affected page; provider-native web fetching is not affected. DetailsNested block elements cause HTML-to-Markdown conversion t...

PYSEC-2026-4281 Pydantic AI: Excessive resource use when local web fetching converts nested HTML

Summary Applications using Pydantic AI's local web-fetch tool can experience excessive CPU and memory use when it converts attacker-controlled HTML. An agent must fetch the affected page; provider-native web fetching is not affected. Details Nested block elements cause HTML-to-Markdown conversion...

Pydantic AI: Excessive resource use when local web fetching converts nested HTML

SummaryApplications using Pydantic AI's local web-fetch tool can experience excessive CPU and memory use when it converts attacker-controlled HTML. An agent must fetch the affected page; provider-native web fetching is not affected. DetailsNested block elements cause HTML-to-Markdown conversion t...

GHSA-V36G-JCW9-X7CW Pydantic AI: Excessive resource use when local web fetching converts nested HTML

Summary Applications using Pydantic AI's local web-fetch tool can experience excessive CPU and memory use when it converts attacker-controlled HTML. An agent must fetch the affected page; provider-native web fetching is not affected. Details Nested block elements cause HTML-to-Markdown conversion...

Pydantic AI: Excessive resource use when local web fetching converts nested HTML

Summary Applications using Pydantic AI's local web-fetch tool can experience excessive CPU and memory use when it converts attacker-controlled HTML. An agent must fetch the affected page; provider-native web fetching is not affected. Details Nested block elements cause HTML-to-Markdown conversion...

CVE-2026-107287 Pydantic AI: Excessive resource use when local web fetching converts nested HTML

Pydantic AI is a Python agent framework for building applications and workflows with Generative AI. From 1.77.0 until 1.107.7 and 2.52.0, the local webfetchtool and the WebFetch local fallback can consume excessive CPU and memory during HTML-to-Markdown conversion of attacker-controlled HTML...