CVE-2026-3514 json
Authentication Bypass in prefecthq/prefect
published 5mo ago modified last mo. also GHSA-c635-393c-hcx2 , PYSEC-2026-2261 , EUVD-2026-33884
- cvss
- 7.5
- version 3.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 41%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- pypi prefect 3.6.22, 3.6.22.dev7
- prefecthq prefecthq/prefect 3.6.22
Is CVE-2026-3514 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 5mo ago
Exploit prediction
0.48% chance of exploitation in the next 30 days, higher than 41% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- huntr.com https://huntr.com/bounties/c540e5e1-f74f-44f4-bfa0-9764ff6daa75 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.0 | 7.5 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| OSV | 3.0 | 7.5 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| GitHub | 3.0 | 7.5 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | prefect | <3.6.22.dev7 <3.6.22 |
3.6.22.dev7 3.6.22 |
Affected products
- prefecthq prefecthq/prefect
Classification
- Weakness
-
- CWE-863 Incorrect Authorization
References
-
github.com
/prefecthq/prefect/commit/e21617125335025b4b27e7d6f0ca028e8e8f3b79
web, patch
-
huntr.com
/bounties/c540e5e1-f74f-44f4-bfa0-9764ff6daa75
exploit, web, third-party-advisory, evidence
-
nvd.nist.gov
/vuln/detail/CVE-2026-3514
advisory
-
github.com
/PrefectHQ/prefect
package
-
github.com
/advisories/GHSA-c635-393c-hcx2
advisory
Sources
- CVE List CVE-2026-3514
- GitHub Advisory GHSA-c635-393c-hcx2
- NVD CVE-2026-3514
- OSV PYSEC-2026-2261
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.