Pydantic AI up to 1.107.1/2.23.x WebFetch buffer overflow

Summaryinfo

A vulnerability categorized as problematic has been discovered in Pydantic AI up to 1.107.1/2.23.x. Impacted is an unknown function of the component WebFetch. Executing a manipulation can lead to buffer overflow. This vulnerability is handled as CVE-2026-107294. The attack can be executed remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in Pydantic AI up to 1.107.1/2.23.x. This vulnerability affects an unknown functionality of the component WebFetch. The manipulation with an unknown input leads to a buffer overflow vulnerability. The CWE definition for the vulnerability is CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. As an impact it is known to affect availability. CVE summarizes:

Pydantic AI is a Python agent framework for building applications and workflows with Generative AI. From 1.77.0 until 1.107.2 and 2.24.0, web_fetch_tool, the WebFetch local fallback, and remote FileUrl media downloads buffer the complete HTTP response body before enforcing content-size controls. An attacker-influenced URL can stream an arbitrarily large response that exhausts process memory and crashes the worker; affected media types include ImageUrl, DocumentUrl, VideoUrl, and AudioUrl. SSRF protections remain effective, and the impact is limited to availability. This issue is fixed in versions 1.107.2 and 2.24.0.

The advisory is available at github.com. This vulnerability was named CVE-2026-107294 since 10/07/2026. The exploitation appears to be easy. The attack can be initiated remotely. The technical details are unknown and an exploit is not available.

Upgrading to version 1.107.2 or 2.24.0 eliminates this vulnerability.

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Productinfo

Type

• Artificial Intelligence Software

Vendor

• Pydantic

Name

• AI

Version

• 1.107.0
• 1.107.1
• 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

CPE 2.3info

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CPE 2.2info

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