{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-107286", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-10-07T15:53:23.586Z", "datePublished": "2026-10-08T15:12:26.597Z", "dateUpdated": "2026-10-08T15:12:26.597Z"}, "containers": {"cna": {"title": "Pydantic AI: Concurrency-limited models can keep their slot when a streamed request ends early", "problemTypes": [{"descriptions": [{"cweId": "CWE-772", "lang": "en", "description": "CWE-772: Missing Release of Resource after Effective Lifetime", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}}], "references": [{"name": "https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-6fqq-452j-qhrp", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-6fqq-452j-qhrp"}, {"name": "https://github.com/pydantic/pydantic-ai/pull/9478", "tags": ["x_refsource_MISC"], "url": "https://github.com/pydantic/pydantic-ai/pull/9478"}, {"name": "https://github.com/pydantic/pydantic-ai/commit/453f19feeb7ab1d789f9393b1723c6a73b3d77b2", "tags": ["x_refsource_MISC"], "url": "https://github.com/pydantic/pydantic-ai/commit/453f19feeb7ab1d789f9393b1723c6a73b3d77b2"}, {"name": "https://github.com/pydantic/pydantic-ai/releases/tag/v2.53.0", "tags": ["x_refsource_MISC"], "url": "https://github.com/pydantic/pydantic-ai/releases/tag/v2.53.0"}], "affected": [{"vendor": "pydantic", "product": "pydantic-ai", "versions": [{"version": ">= 2.10.0, < 2.53.0", "status": "affected"}]}, {"vendor": "pydantic", "product": "pydantic-ai-slim", "versions": [{"version": ">= 2.10.0, < 2.53.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-10-08T15:12:26.597Z"}, "descriptions": [{"lang": "en", "value": "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."}], "source": {"advisory": "GHSA-6fqq-452j-qhrp", "discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"product": "pydantic-ai", "vendor": "pydantic", "versions": [{"status": "affected", "version": ">= 2.10.0, < 2.53.0"}]}, {"product": "pydantic-ai-slim", "vendor": "pydantic", "versions": [{"status": "affected", "version": ">= 2.10.0, < 2.53.0"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "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", "lastModified": "2026-10-08T15:17:40.753", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-10-08T15:17:40.753", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/pydantic/pydantic-ai/commit/453f19feeb7ab1d789f9393b1723c6a73b3d77b2"}, {"source": "security-advisories@github.com", "url": "https://github.com/pydantic/pydantic-ai/pull/9478"}, {"source": "security-advisories@github.com", "url": "https://github.com/pydantic/pydantic-ai/releases/tag/v2.53.0"}, {"source": "security-advisories@github.com", "url": "https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-6fqq-452j-qhrp"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-772"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{}