6.8
MEDIUM CVSS 3.1
CVE-2026-54249
VercelAIAdapter trusts client-controlled `providerMetadata` to construct `UploadedFile` — S3/GCS confused deputy via provider metadata injection
Description

Pydantic AI is a Python agent framework for building Generative AI applications. In versions 1.65.0 through 1.105.0, and 2.0.0b1 through 2.0.0b5, a client that submits message history to a Pydantic AI UI adapter (such as the Vercel AI adapter) can reference arbitrary files in the application's model-provider or cloud-storage account. While file URL parts are validated against a scheme allowlist, UploadedFile references — which point to a file by provider file ID or cloud-storage URI (e.g. s3://…, gs://…) — were forwarded without validation. Because the provider resolves an UploadedFile using the server-side identity (IAM role, service account, or provider API key) rather than the client's, an attacker can craft message history to make the server read objects from its own account or other tenants, given a referenceable identifier. Exploitation requires a valid file identifier, which is not always unguessable depending on how the application names objects. This issue has been fixed in versions 1.106.0 and 2.0.0b6.

INFO

Published Date :

July 29, 2026, 9:17 p.m.

Last Modified :

July 29, 2026, 9:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-54249 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update Pydantic AI agent framework to fix file upload validation vulnerability.
  • Update Pydantic AI agent framework to version 1.106.0 or later.
  • If using Pydantic AI 2.0.0b, update to 2.0.0b6 or later.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-54249.

URL Resource
https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-h7p7-w5gc-xj3w
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-54249 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-54249 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-54249 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-54249 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jul. 29, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'pydantic', 'product': 'pydantic-ai', 'versions': [{'status': 'affected', 'version': '>= 1.65.0, < 1.106.0'}, {'status': 'affected', 'version': '>= 2.0.0b1, < 2.0.0b6'}]}, {'vendor': 'pydantic', 'product': 'pydantic-ai-slim', 'versions': [{'status': 'affected', 'version': '>= 2.0.0b1, < 2.0.0b6'}, {'status': 'affected', 'version': '>= 1.65.0, < 1.106.0'}]}]
    Added Description Pydantic AI is a Python agent framework for building Generative AI applications. In versions 1.65.0 through 1.105.0, and 2.0.0b1 through 2.0.0b5, a client that submits message history to a Pydantic AI UI adapter (such as the Vercel AI adapter) can reference arbitrary files in the application's model-provider or cloud-storage account. While file URL parts are validated against a scheme allowlist, UploadedFile references — which point to a file by provider file ID or cloud-storage URI (e.g. s3://…, gs://…) — were forwarded without validation. Because the provider resolves an UploadedFile using the server-side identity (IAM role, service account, or provider API key) rather than the client's, an attacker can craft message history to make the server read objects from its own account or other tenants, given a referenceable identifier. Exploitation requires a valid file identifier, which is not always unguessable depending on how the application names objects. This issue has been fixed in versions 1.106.0 and 2.0.0b6.
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N
    Added CWE CWE-918
    Added Reference https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-h7p7-w5gc-xj3w
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.