{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "2.10.0"
              },
              {
                "fixed": "2.53.0"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "d8b95a48466e99963042d2bd3164c6fdc227e6d4"
            },
            {
              "fixed": "b38ab5d955394144296100d3c41599c003973722"
            }
          ],
          "repo": "https://github.com/pydantic/pydantic-ai",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-6fqq-452j-qhrp"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-772"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/107xxx/CVE-2026-107286.json"
  },
  "details": "Pydantic AI is a Python agent framework for building applications and workflows with Generative AI. From 2.10.0 until 2.53.0, streamed requests made through ConcurrencyLimitedModel or limit_model_concurrency can retain shared concurrency slots because anyio.CapacityLimiter associates an acquired slot with the borrowing task while streaming cleanup can run in a different task. Early stream termination, cancellation, consumer exceptions, or complete stream_text() consumption with debounce_by=0.1 can therefore leave capacity occupied, eventually preventing later requests that share the long-lived limiter from proceeding and causing a denial of service. Agent-level max_concurrency and non-streaming model requests are not affected. This issue is fixed in version 2.53.0.",
  "id": "CVE-2026-107286",
  "modified": "2026-10-09T02:30:28.856966736Z",
  "published": "2026-10-08T15:12:26.597Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/107xxx/CVE-2026-107286.json"
    },
    {
      "type": "FIX",
      "url": "https://github.com/pydantic/pydantic-ai/commit/453f19feeb7ab1d789f9393b1723c6a73b3d77b2"
    },
    {
      "type": "FIX",
      "url": "https://github.com/pydantic/pydantic-ai/pull/9478"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pydantic/pydantic-ai/releases/tag/v2.53.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-6fqq-452j-qhrp"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-107286"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Pydantic AI: Concurrency-limited models can keep their slot when a streamed request ends early"
}