Local Web Fetching Vulnerability in Pydantic AI Framework
CVE-2026-107288

3.7LOW

Key Information:

Vendor

Pydantic

Status
Pydantic-ai
Pydantic-ai-slim
Vendor
CVE Published:
8 October 2026

What is CVE-2026-107288?

A local web fetching vulnerability exists in the Pydantic AI framework due to improper validation of domain entries in the web_fetch_tool component. Attackers can exploit this flaw by manipulating an application to fetch content from a blocked domain using misleading variations of the URL. Even when protected by domain restrictions, the application’s retrieval mechanisms can be bypassed when the input is normalized incorrectly. While protections against private IPs and cloud metadata are intact, it is crucial to update to versions 1.107.6 or 2.44.0, which address this security issue.

Affected Version(s)

pydantic-ai >= 1.77.0, < 1.107.6 < 1.77.0, 1.107.6

pydantic-ai >= 2.0.0b1, < 2.44.0 < 2.0.0b1, 2.44.0

pydantic-ai-slim >= 1.77.0, < 1.107.6 < 1.77.0, 1.107.6

References

https://github.com/pydantic/pydantic-ai/security/advisori...
x_refsource_CONFIRM
https://github.com/pydantic/pydantic-ai/pull/8407
x_refsource_MISC
https://github.com/pydantic/pydantic-ai/pull/8409
x_refsource_MISC

CVSS V3.1

Score:
3.7
Severity:
LOW
Confidentiality:
Low
Integrity:
None
Availability:
Low
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.