{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "1.77.0"
              },
              {
                "fixed": "1.107.7"
              },
              {
                "introduced": "2.0.0b1"
              },
              {
                "fixed": "2.52.0"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "a282bcade2c2a75847806bbba9cf511dd0623019"
            },
            {
              "introduced": "6001a4549018ad5509f2c11ed6c38d2385159506"
            },
            {
              "fixed": "2fd38792693da00a3ca5412aeffb436787af3545"
            },
            {
              "fixed": "4de1ee3cf6026caa7f58b293ae929a1130b6b388"
            },
            {
              "fixed": "2b247add4950bef61d352e7ca8aefbd20539180c"
            }
          ],
          "repo": "https://github.com/pydantic/pydantic-ai",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-v36g-jcw9-x7cw"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-400",
      "CWE-407"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/107xxx/CVE-2026-107287.json"
  },
  "details": "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.",
  "id": "CVE-2026-107287",
  "modified": "2026-10-10T02:30:42.541783096Z",
  "published": "2026-10-08T15:15:05.417Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/pydantic/pydantic-ai/releases/tag/v1.107.7"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pydantic/pydantic-ai/releases/tag/v2.52.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/107xxx/CVE-2026-107287.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-v36g-jcw9-x7cw"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-107287"
    },
    {
      "type": "FIX",
      "url": "https://github.com/pydantic/pydantic-ai/commit/2b247add4950bef61d352e7ca8aefbd20539180c"
    },
    {
      "type": "FIX",
      "url": "https://github.com/pydantic/pydantic-ai/commit/2fd38792693da00a3ca5412aeffb436787af3545"
    },
    {
      "type": "FIX",
      "url": "https://github.com/pydantic/pydantic-ai/pull/8984"
    },
    {
      "type": "FIX",
      "url": "https://github.com/pydantic/pydantic-ai/pull/8985"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Pydantic AI: Excessive resource use when local web fetching converts nested HTML"
}