CVE-2026-107288lowCWE-1289CWE-918

CVE-2026-107288: fallo de gravedad baja en pydantic-ai

Pydantic AI: web_fetch_tool blocked_domains bypass via a hostname the resolver normalizes differently

Publicada el

Seguir esta CVE+ Monitorear pydantic-ai+ Monitorear pydantic-ai-slim

Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.

8Vexday Risk Score

Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.

ssvc Trackcvss 3.7epss 0.4%
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:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
Productos afectados
pydantic · pydantic-aipydantic · pydantic-ai-slim
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