{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-107288", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-10-07T15:53:23.586Z", "datePublished": "2026-10-08T15:18:40.047Z", "dateUpdated": "2026-10-08T15:18:40.047Z"}, "containers": {"cna": {"title": "Pydantic AI: web_fetch_tool blocked_domains bypass via a hostname the resolver normalizes differently", "problemTypes": [{"descriptions": [{"cweId": "CWE-918", "lang": "en", "description": "CWE-918: Server-Side Request Forgery (SSRF)", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-1289", "lang": "en", "description": "CWE-1289: Improper Validation of Unsafe Equivalence in Input", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 3.7, "baseSeverity": "LOW", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-22h6-qm39-v87j", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-22h6-qm39-v87j"}, {"name": "https://github.com/pydantic/pydantic-ai/pull/8407", "tags": ["x_refsource_MISC"], "url": "https://github.com/pydantic/pydantic-ai/pull/8407"}, {"name": "https://github.com/pydantic/pydantic-ai/pull/8409", "tags": ["x_refsource_MISC"], "url": "https://github.com/pydantic/pydantic-ai/pull/8409"}, {"name": "https://github.com/pydantic/pydantic-ai/pull/8421", "tags": ["x_refsource_MISC"], "url": "https://github.com/pydantic/pydantic-ai/pull/8421"}, {"name": "https://github.com/pydantic/pydantic-ai/commit/490335f8e2322e143a79337ddca9410e0176c812", "tags": ["x_refsource_MISC"], "url": "https://github.com/pydantic/pydantic-ai/commit/490335f8e2322e143a79337ddca9410e0176c812"}, {"name": "https://github.com/pydantic/pydantic-ai/commit/a9dab92099d0ef9d5d4aa34ccac8a6f1b0e51284", "tags": ["x_refsource_MISC"], "url": "https://github.com/pydantic/pydantic-ai/commit/a9dab92099d0ef9d5d4aa34ccac8a6f1b0e51284"}, {"name": "https://github.com/pydantic/pydantic-ai/commit/c1f212a084cbfa0012f2044cdb4731d214b3b983", "tags": ["x_refsource_MISC"], "url": "https://github.com/pydantic/pydantic-ai/commit/c1f212a084cbfa0012f2044cdb4731d214b3b983"}, {"name": "https://github.com/pydantic/pydantic-ai/releases/tag/v1.107.6", "tags": ["x_refsource_MISC"], "url": "https://github.com/pydantic/pydantic-ai/releases/tag/v1.107.6"}, {"name": "https://github.com/pydantic/pydantic-ai/releases/tag/v2.44.0", "tags": ["x_refsource_MISC"], "url": "https://github.com/pydantic/pydantic-ai/releases/tag/v2.44.0"}], "affected": [{"vendor": "pydantic", "product": "pydantic-ai", "versions": [{"version": ">= 1.77.0, < 1.107.6", "status": "affected"}, {"version": ">= 2.0.0b1, < 2.44.0", "status": "affected"}]}, {"vendor": "pydantic", "product": "pydantic-ai-slim", "versions": [{"version": ">= 1.77.0, < 1.107.6", "status": "affected"}, {"version": ">= 2.0.0b1, < 2.44.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-10-08T15:18:40.047Z"}, "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."}], "source": {"advisory": "GHSA-22h6-qm39-v87j", "discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"product": "pydantic-ai", "vendor": "pydantic", "versions": [{"status": "affected", "version": ">= 1.77.0, < 1.107.6"}, {"status": "affected", "version": ">= 2.0.0b1, < 2.44.0"}]}, {"product": "pydantic-ai-slim", "vendor": "pydantic", "versions": [{"status": "affected", "version": ">= 1.77.0, < 1.107.6"}, {"status": "affected", "version": ">= 2.0.0b1, < 2.44.0"}]}], "source": "[email protected]"}], "cveTags": [], "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."}], "id": "CVE-2026-107288", "lastModified": "2026-10-08T16:17:04.147", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 3.7, "baseSeverity": "LOW", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 2.2, "impactScore": 1.4, "source": "[email protected]", "type": "Secondary"}]}, "published": "2026-10-08T16:17:04.147", "references": [{"source": "[email protected]", "url": "https://github.com/pydantic/pydantic-ai/commit/490335f8e2322e143a79337ddca9410e0176c812"}, {"source": "[email protected]", "url": "https://github.com/pydantic/pydantic-ai/commit/a9dab92099d0ef9d5d4aa34ccac8a6f1b0e51284"}, {"source": "[email protected]", "url": "https://github.com/pydantic/pydantic-ai/commit/c1f212a084cbfa0012f2044cdb4731d214b3b983"}, {"source": "[email protected]", "url": "https://github.com/pydantic/pydantic-ai/pull/8407"}, {"source": "[email protected]", "url": "https://github.com/pydantic/pydantic-ai/pull/8409"}, {"source": "[email protected]", "url": "https://github.com/pydantic/pydantic-ai/pull/8421"}, {"source": "[email protected]", "url": "https://github.com/pydantic/pydantic-ai/releases/tag/v1.107.6"}, {"source": "[email protected]", "url": "https://github.com/pydantic/pydantic-ai/releases/tag/v2.44.0"}, {"source": "[email protected]", "url": "https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-22h6-qm39-v87j"}], "sourceIdentifier": "[email protected]", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-918"}, {"lang": "en", "value": "CWE-1289"}], "source": "[email protected]", "type": "Primary"}]}

{}

{}