CVE-2026-107290

Pydantic AI is a Python agent framework for building applications and workflows with Generative AI. From 1.77.0 until 1.107.6 and 2.44.0, the local web_fetch_tool and the WebFetch local fallback process server-controlled responses with quadratic title extraction, whitespace normalization, and ordered-list numbering. An attacker-controlled page of modest size can therefore block the event loop for an extended period, stalling other agent runs and requests, while unsupported codecs or excessive HTML or JSON nesting can abort an individual run. This issue is fixed in versions 1.107.6 and 2.44.0.
Configurations

Configuration 1 (hide)

OR cpe:2.3:a:pydantic:pydantic_ai:*:*:*:*:*:python:*:*
cpe:2.3:a:pydantic:pydantic_ai:*:-:*:*:*:python:*:*

History

13 Oct 2026, 14:34

Type Values Removed Values Added
CPE cpe:2.3:a:pydantic:pydantic_ai:*:-:*:*:*:python:*:*
cpe:2.3:a:pydantic:pydantic_ai:*:*:*:*:*:python:*:*
References () https://github.com/pydantic/pydantic-ai/commit/2faa6181d8a17d83bc9516d035c5270db8730fa0 - () https://github.com/pydantic/pydantic-ai/commit/2faa6181d8a17d83bc9516d035c5270db8730fa0 - Patch
References () https://github.com/pydantic/pydantic-ai/commit/9cdc952e4c3319e85a3e04f2de49fbbb765bd38b - () https://github.com/pydantic/pydantic-ai/commit/9cdc952e4c3319e85a3e04f2de49fbbb765bd38b - Patch
References () https://github.com/pydantic/pydantic-ai/commit/a93ea5226be1e93ae13131ae3f22287190411389 - () https://github.com/pydantic/pydantic-ai/commit/a93ea5226be1e93ae13131ae3f22287190411389 - Patch
References () https://github.com/pydantic/pydantic-ai/commit/c3fd1cc1f15fdbf750d78e4e3ec1e8b4d6a3d920 - () https://github.com/pydantic/pydantic-ai/commit/c3fd1cc1f15fdbf750d78e4e3ec1e8b4d6a3d920 - Exploit, Patch
References () https://github.com/pydantic/pydantic-ai/commit/fb92ccfc3ca2735dab877e2ed73856681bf72ad1 - () https://github.com/pydantic/pydantic-ai/commit/fb92ccfc3ca2735dab877e2ed73856681bf72ad1 - Patch
References () https://github.com/pydantic/pydantic-ai/pull/8397 - () https://github.com/pydantic/pydantic-ai/pull/8397 - Patch, Vendor Advisory
References () https://github.com/pydantic/pydantic-ai/pull/8399 - () https://github.com/pydantic/pydantic-ai/pull/8399 - Patch, Vendor Advisory
References () https://github.com/pydantic/pydantic-ai/pull/8418 - () https://github.com/pydantic/pydantic-ai/pull/8418 - Patch, Vendor Advisory
References () https://github.com/pydantic/pydantic-ai/pull/84332 - () https://github.com/pydantic/pydantic-ai/pull/84332 - Broken Link
References () https://github.com/pydantic/pydantic-ai/pull/8434 - () https://github.com/pydantic/pydantic-ai/pull/8434 - Patch, Vendor Advisory
References () https://github.com/pydantic/pydantic-ai/releases/tag/v1.107.6 - () https://github.com/pydantic/pydantic-ai/releases/tag/v1.107.6 - Patch, Release Notes, Vendor Advisory
References () https://github.com/pydantic/pydantic-ai/releases/tag/v2.44.0 - () https://github.com/pydantic/pydantic-ai/releases/tag/v2.44.0 - Patch, Release Notes, Vendor Advisory
References () https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-fpf4-vwcp-v4hp - () https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-fpf4-vwcp-v4hp - Vendor Advisory
First Time Pydantic
Pydantic pydantic Ai

08 Oct 2026, 17:17

Type Values Removed Values Added
New CVE

Information

Published : 2026-10-08 17:17

Updated : 2026-10-13 14:34


NVD link : CVE-2026-107290

Mitre link : CVE-2026-107290

CVE.ORG link : CVE-2026-107290


JSON object : View

Products Affected

pydantic

  • pydantic_ai
CWE
CWE-1333

Inefficient Regular Expression Complexity