Vulnerability · Published Jun 2, 2026 · Assigned by @huntr_ai

CVE-2026-3514Authentication Bypass in prefecthq/prefect

High 7.5

In plain English

A high-severity incorrect authorization in prefecthq/prefect from prefecthq. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 41% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.0)7.5High
Exploit odds (30 days)0.5%top 58.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
PyPIprefect3.6.22.dev7GHSA-c635-393c-hcx2
PyPIprefect3.6.22PYSEC-2026-2261

Affected products (as reported)

VendorProductVersions
prefecthq prefecthq/prefect unspecified – before 3.6.22

Weakness: CWE-863 · Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

References