Prefect has an Authentication Middleware Bypass when URL paths are appended with 'health' or 'ready'
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 software
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| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Python (PyPI) | prefect | < 3.6.22.dev7 | 3.6.22.dev7 |
References
- CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N- Weakness (CWE)
CWE-863- Platform
- Python (PyPI)
- Package
prefect- Disclosed
- 02.06.2026
- Updated
- 11.10.2026 15:17
Sources and licenses
OSV / GitHub Advisory Database - PYSEC-2026-2261 - PyPA Advisory Database; CC BY 4.0
OSV / GitHub Advisory Database - GHSA-c635-393c-hcx2 - CC BY 4.0
Vulnerability history: prefect
All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 8
- First → latest
- 11.2023 06.2026
- Without a fix
- 1
- Exploited in attacks
- 0
Severity breakdown
- High 4
- Medium 2
- Low 2
Disclosures per year
- 2023: 1
- 2024: 0
- 2025: 1
- 2026: 6
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Prefect has an Authentication Middleware Bypass when URL paths are appended with 'health' or 'ready' this entry
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