« Back to list

CVE-2026-107288

Status: AnalyzedLow (3.7)—

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 compare blocked_domains entries with a URL hostname before both values are normalized to the form used by getaddrinfo. An attacker-influenced model can use an equivalent IDNA spelling, non-ASCII label separator, case variation, or trailing root label that resolves to a blocked host but does not match the configured string, causing the application to fetch that host with its own privileges. allowed_domains fails closed for unmatched spellings, and private-IP and cloud-metadata protections remain effective. This issue is fixed in versions 1.107.6 and 2.44.0.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

AV:N sin UI:N sugiere T1190. La vulnerabilidad permite SSRF mediante evasión de filtros de dominio (bypass de blocked_domains con variantes IDNA), accediendo a metadatos o hosts internos con privilegios de la aplicación.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Privileged Account ManagementNetwork SegmentationLimit Access to Resource Over NetworkVulnerability ScanningUser Account ManagementSSL/TLS Inspection

Affected technologies (1)

Pydantic — Pydantic AI

CWEs

References

Raw JSON (NVD)

Show
{
  "id": "CVE-2026-107288",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-107288",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-10-08T17:28:31.014859Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "security-advisories@github.com",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 3.7,
          "attackVector": "NETWORK",
          "baseSeverity": "LOW",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "HIGH",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "LOW"
        },
        "impactScore": 1.4,
        "exploitabilityScore": 2.2
      }
    ]
  },
  "affected": [
    {
      "source": "security-advisories@github.com",
      "affectedData": [
        {
          "vendor": "pydantic",
          "product": "pydantic-ai",
          "versions": [
            {
              "status": "affected",
              "version": ">= 1.77.0, < 1.107.6"
            },
            {
              "status": "affected",
              "version": ">= 2.0.0b1, < 2.44.0"
            }
          ]
        },
        {
          "vendor": "pydantic",
          "product": "pydantic-ai-slim",
          "versions": [
            {
              "status": "affected",
              "version": ">= 1.77.0, < 1.107.6"
            },
            {
              "status": "affected",
              "version": ">= 2.0.0b1, < 2.44.0"
            }
          ]
        }
      ]
    }
  ],
  "published": "2026-10-08T16:17:04.147",
  "references": [
    {
      "url": "https://github.com/pydantic/pydantic-ai/commit/490335f8e2322e143a79337ddca9410e0176c812",
      "tags": [
        "Patch"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/pydantic/pydantic-ai/commit/a9dab92099d0ef9d5d4aa34ccac8a6f1b0e51284",
      "tags": [
        "Patch"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/pydantic/pydantic-ai/commit/c1f212a084cbfa0012f2044cdb4731d214b3b983",
      "tags": [
        "Patch"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/pydantic/pydantic-ai/pull/8407",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/pydantic/pydantic-ai/pull/8409",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/pydantic/pydantic-ai/pull/8421",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/pydantic/pydantic-ai/releases/tag/v1.107.6",
      "tags": [
        "Patch",
        "Release Notes",
        "Vendor Advisory"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/pydantic/pydantic-ai/releases/tag/v2.44.0",
      "tags": [
        "Patch",
        "Release Notes",
        "Vendor Advisory"
      ],
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-22h6-qm39-v87j",
      "tags": [
        "Mitigation",
        "Vendor Advisory"
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "security-advisories@github.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-918"
        },
        {
          "lang": "en",
          "value": "CWE-1289"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "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 compare blocked_domains entries with a URL hostname before both values are normalized to the form used by getaddrinfo. An attacker-influenced model can use an equivalent IDNA spelling, non-ASCII label separator, case variation, or trailing root label that resolves to a blocked host but does not match the configured string, causing the application to fetch that host with its own privileges. allowed_domains fails closed for unmatched spellings, and private-IP and cloud-metadata protections remain effective. This issue is fixed in versions 1.107.6 and 2.44.0."
    }
  ],
  "lastModified": "2026-10-13T14:35:05.370",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:pydantic:pydantic_ai:*:*:*:*:*:python:*:*",
              "vulnerable": true,
              "matchCriteriaId": "B5355402-6E86-4212-A795-993C09433A3C",
              "versionEndExcluding": "1.107.6",
              "versionStartIncluding": "1.77.0"
            },
            {
              "criteria": "cpe:2.3:a:pydantic:pydantic_ai:*:-:*:*:*:python:*:*",
              "vulnerable": true,
              "matchCriteriaId": "7FEC7EC8-5520-4930-8853-83108092F8BF",
              "versionEndExcluding": "2.44.0",
              "versionStartIncluding": "2.0.0"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "security-advisories@github.com"
}