CVE-2026-107286

{
  "etk_id": "ETK-2026-342",
  "cve_id": "CVE-2026-107286",
  "display_id": "CVE-2026-107286",
  "ghsa_id": "GHSA-6fqq-452j-qhrp",
  "euvd_id": "EUVD-2026-95039",
  "status": "published",
  "anchor_state": "anchored",
  "title": "Streaming concurrency slot leak in pydantic-ai",
  "summary": "pydantic-ai and pydantic-ai-slim before 2.53.0 can retain shared concurrency capacity after streaming requests made through a concurrency-limited model. A client able to access a streaming endpoint may exhaust a long-lived shared limiter and block later requests, particularly when streams are interrupted; non-streaming requests and agent-level concurrency limits are not affected.",
  "mitigation": "Upgrade pydantic-ai or pydantic-ai-slim to version 2.53.0. Until upgrade, use agent-level max_concurrency rather than a concurrency-limited model, or disable streaming on models using that limiter.",
  "vendor": "pip",
  "product": "pip:pydantic-ai",
  "affected": [
    {
      "affected_notes": [],
      "affected_ranges": [
        ">= 2.10.0, < 2.53.0"
      ],
      "ecosystem": "pip",
      "fixed_versions": [
        "2.53.0"
      ],
      "package_name": "pydantic-ai",
      "purl": "pkg:pypi/pydantic-ai"
    },
    {
      "affected_notes": [],
      "affected_ranges": [
        ">= 2.10.0, < 2.53.0"
      ],
      "ecosystem": "pip",
      "fixed_versions": [
        "2.53.0"
      ],
      "package_name": "pydantic-ai-slim",
      "purl": "pkg:pypi/pydantic-ai-slim"
    }
  ],
  "cwes": [
    772
  ],
  "cvss_score": 7.5,
  "cvss_src": "cna_vendor",
  "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
  "epss_score": 0.0045,
  "epss_percentile": 0.3778,
  "epss_asof": "2026-10-20",
  "automation": "contextual",
  "check": false,
  "check_confidence_basis": null,
  "exploit": false,
  "pipeline_minutes": 10.612766616666667,
  "t0_at": "2026-10-08T15:12:26.597000+00:00",
  "signals": {
    "trigger_signal": {
      "at": "2026-10-02T03:19:39+00:00",
      "days": -6.494995335648148,
      "is_lower_bound": false,
      "measured_at": "2026-10-08T15:12:26.597000+00:00",
      "url": "https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-6fqq-452j-qhrp"
    }
  }
}