---
title: "CVE-2026-107286: Pydantic AI - Denial of Service"
description: "Pydantic AI 2.10.0 to 2.53.0 contains a denial of service caused by concurrency slot retention in streamed requests via ConcurrencyLimitedModel or limit_model_concurrency, letting attackers block later requests, exploit requires use of shared concurrency limiter with streaming."
url: https://panop.io/threat-heartbeat/CVE-2026-107286/
---

# CVE-2026-107286 Pydantic AI - Denial of Service

Pydantic AI 2.10.0 to 2.53.0 contains a denial of service caused by concurrency slot retention in streamed requests via ConcurrencyLimitedModel or limit\_model\_concurrency, letting attackers block later requests, exploit requires use of shared concurrency limiter with streaming.

CVSS base score 7.5 /10

High

CISA KEV

Not listed

Public exploit

None known

Authentication

Not required

EPSS

0.45% chance of exploitation in 30 days

[View the NVD record ↗](https://nvd.nist.gov/vuln/detail/CVE-2026-107286)

## Details

Type

Denial of Service

Impact

Denial Of Service

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Published

8 October 2026

Updated

15 October 2026

Weakness

[CWE-772](https://cwe.mitre.org/data/definitions/772.html)

## Vendor fix

Update to version 2.53.0 or later.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

## References

- [https://nvd.nist.gov/vuln/detail/CVE-2026-107286](https://nvd.nist.gov/vuln/detail/CVE-2026-107286)
- [https://github.com/pydantic/pydantic-ai/commit/453f19feeb7ab1d789f9393b1723c6a73b3d77b2](https://github.com/pydantic/pydantic-ai/commit/453f19feeb7ab1d789f9393b1723c6a73b3d77b2)
- [https://github.com/pydantic/pydantic-ai/pull/9478](https://github.com/pydantic/pydantic-ai/pull/9478)
- [https://github.com/pydantic/pydantic-ai/releases/tag/v2.53.0](https://github.com/pydantic/pydantic-ai/releases/tag/v2.53.0)
- [https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-6fqq-452j-qhrp](https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-6fqq-452j-qhrp)

[← All CVEs](https://panop.io/threat-heartbeat/)

## What this record can't tell you

- Whether you run the affected software, and where
- Whether an attacker can actually reach and exploit it
- The misconfigurations that never get a CVE number
- What it would cost the business, ranked into what to fix first

Panop answers these inside your environment, for this CVE and every other finding.

[Book a demo](https://panop.io/demo)