{"id":"CVE-2026-107287","title":"Pydantic AI is a Python agent framework for building applications and workflows with Generative AI","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 durin…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","cwe":["CWE-400","CWE-407"],"vendor":"pydantic","product":"pydantic-ai","affected":["pydantic-ai >= 1.77.0, < 1.107.7","pydantic-ai >= 2.0.0b1, < 2.52.0","pydantic-ai-slim >= 1.77.0, < 1.107.7","pydantic-ai-slim >= 2.0.0b1, < 2.52.0"],"patched":["pydantic-ai 1.107.7","pydantic-ai 2.52.0","pydantic-ai-slim 1.107.7","pydantic-ai-slim 2.52.0"],"published":"2026-10-08","updated":"2026-10-08","sourceUpdated":"2026-10-08T21:05:00.260","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-107287","references":[{"url":"https://github.com/pydantic/pydantic-ai/commit/2b247add4950bef61d352e7ca8aefbd20539180c","label":"security-advisories@github.com"},{"url":"https://github.com/pydantic/pydantic-ai/commit/2fd38792693da00a3ca5412aeffb436787af3545","label":"security-advisories@github.com"},{"url":"https://github.com/pydantic/pydantic-ai/pull/8984","label":"security-advisories@github.com"},{"url":"https://github.com/pydantic/pydantic-ai/pull/8985","label":"security-advisories@github.com"},{"url":"https://github.com/pydantic/pydantic-ai/releases/tag/v1.107.7","label":"security-advisories@github.com"},{"url":"https://github.com/pydantic/pydantic-ai/releases/tag/v2.52.0","label":"security-advisories@github.com"},{"url":"https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-v36g-jcw9-x7cw","label":"security-advisories@github.com"},{"url":"https://github.com/advisories/GHSA-v36g-jcw9-x7cw"}],"tags":["nvd","cve.org","ghsa","pip"],"aliases":["GHSA-v36g-jcw9-x7cw"],"ecosystem":"pip","ingestedAt":"2026-10-08T16:52:14.772Z","slug":"CVE-2026-107287","body":"## Overview\n\nPydantic 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-107287)\n\nAffected packages:\n\n- `pydantic-ai >= 1.77.0, < 1.107.7`\n- `pydantic-ai >= 2.0.0b1, < 2.52.0`\n- `pydantic-ai-slim >= 1.77.0, < 1.107.7`\n- `pydantic-ai-slim >= 2.0.0b1, < 2.52.0`\n\nPatched in:\n\n- `pydantic-ai 1.107.7`\n- `pydantic-ai 2.52.0`\n- `pydantic-ai-slim 1.107.7`\n- `pydantic-ai-slim 2.52.0`\n\nSource: https://github.com/advisories/GHSA-v36g-jcw9-x7cw","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}