CVE-2026-107287 (GCVE-0-2026-107287)

Vulnerability from cvelistv5 – Published: 2026-10-08 15:15 – Updated: 2026-10-08 15:15
VLAI
Title
Pydantic AI: Excessive resource use when local web fetching converts nested HTML
Summary
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 web_fetch_tool and the WebFetch local fallback can consume excessive CPU and memory during HTML-to-Markdown conversion of attacker-controlled HTML containing deeply nested block elements. Conversion repeatedly reprocesses accumulated text and can greatly expand intermediate output before the returned-content limit is applied, allowing a model-directed fetch to delay other work in the process. Provider-native web fetching is not affected. This issue is fixed in versions 1.107.7 and 2.52.0.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-407 - Inefficient Algorithmic Complexity
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7595 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
pydantic pydantic-ai Affected: >= 1.77.0, < 1.107.7
Affected: >= 2.0.0b1, < 2.52.0
guessed Create a notification for this product.
pydantic pydantic-ai-slim Affected: >= 1.77.0, < 1.107.7
Affected: >= 2.0.0b1, < 2.52.0
guessed Create a notification for this product.
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      "metrics": [
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}



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