7.5
HIGH CVSS 3.0
CVE-2026-3514
Authentication Bypass in prefecthq/prefect
Description

In version 3.6.19 of prefecthq/prefect, an authentication bypass vulnerability exists due to the improper handling of URL path exemptions for health check probes. Specifically, the authentication middleware exempts any URL path ending with 'health' or 'ready' from authentication checks. This allows an attacker to create resources with names ending in 'health' or 'ready' and access them without authentication. Affected endpoints include those for variables, flows, work pools, work queues, and deployments. This vulnerability can lead to unauthorized access to sensitive information, such as API keys and database credentials, stored in Prefect Variables.

INFO

Published Date :

June 2, 2026, 9:16 a.m.

Last Modified :

June 2, 2026, 2:35 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-3514 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.

ID Vendor Product Action
1 Prefect prefect
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 3.0 HIGH [email protected]
Solution
Update Prefect to a version that addresses authentication bypass for health check probes.
  • Update Prefect to a fixed version.
  • Review and sanitize resource names.
  • Monitor for unauthorized access attempts.
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-2026-3514.

URL Resource
https://github.com/prefecthq/prefect/commit/e21617125335025b4b27e7d6f0ca028e8e8f3b79
https://huntr.com/bounties/c540e5e1-f74f-44f4-bfa0-9764ff6daa75
https://huntr.com/bounties/c540e5e1-f74f-44f4-bfa0-9764ff6daa75
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-3514 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-2026-3514 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-2026-3514 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-3514 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.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jun. 02, 2026

    Action Type Old Value New Value
    Added Reference https://huntr.com/bounties/c540e5e1-f74f-44f4-bfa0-9764ff6daa75
  • New CVE Received by [email protected]

    Jun. 02, 2026

    Action Type Old Value New Value
    Added Description In version 3.6.19 of prefecthq/prefect, an authentication bypass vulnerability exists due to the improper handling of URL path exemptions for health check probes. Specifically, the authentication middleware exempts any URL path ending with 'health' or 'ready' from authentication checks. This allows an attacker to create resources with names ending in 'health' or 'ready' and access them without authentication. Affected endpoints include those for variables, flows, work pools, work queues, and deployments. This vulnerability can lead to unauthorized access to sensitive information, such as API keys and database credentials, stored in Prefect Variables.
    Added CVSS V3 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
    Added CWE CWE-863
    Added Reference https://github.com/prefecthq/prefect/commit/e21617125335025b4b27e7d6f0ca028e8e8f3b79
    Added Reference https://huntr.com/bounties/c540e5e1-f74f-44f4-bfa0-9764ff6daa75
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.