Pydantic AI up to 1.107.3/2.27.x Clai Web Development Chat Endpoint Agent.to_web input validation

Summaryinfo

A vulnerability identified as critical has been detected in Pydantic AI up to 1.107.3/2.27.x. The affected element is the function Agent.to_web of the component Clai Web Development Chat Endpoint. The manipulation leads to input validation. This vulnerability is uniquely identified as CVE-2026-107295. The attack is possible to be carried out remotely. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Pydantic AI up to 1.107.3/2.27.x. This issue affects the function Agent.to_web of the component Clai Web Development Chat Endpoint. The manipulation with an unknown input leads to a input validation vulnerability. Using CWE to declare the problem leads to CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Pydantic AI is a Python agent framework for building applications and workflows with Generative AI. From 1.34.0 until 1.107.4 and 2.28.0, the Agent.to_web() and clai web development chat endpoint has missing request content-type validation. A website visited by a developer can submit a browser-compatible request to a loopback-hosted chat server, causing the served agent to run and execute tools with the privileges and credentials of the local process; client-relayed approval decisions also leave requires_approval=True tools exposed. Binding to localhost does not prevent a browser page from reaching the loopback address. This issue is fixed in versions 1.107.4 and 2.28.0.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-107295 since 10/07/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 1.107.4 or 2.28.0 eliminates this vulnerability.

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Productinfo

Type

• Artificial Intelligence Software

Vendor

• Pydantic

Name

• AI

Version

• 1.107.0
• 1.107.1
• 1.107.2
• 1.107.3
• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6
• 2.7
• 2.8
• 2.9
• 2.10
• 2.11
• 2.12
• 2.13
• 2.14
• 2.15
• 2.16
• 2.17
• 2.18
• 2.19
• 2.20
• 2.21
• 2.22
• 2.23
• 2.24
• 2.25
• 2.26
• 2.27

CPE 2.3info

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CPE 2.2info

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