CVE-2026-3514: In version 3.6.19 of prefecthq/prefect, an authentication bypass vulnerability exists due to the improper hand

Q: How do I fix CVE-2026-3514?

prefect: upgrade to 3.6.22. Exact commands for each OS are on this page.

Q: Is CVE-2026-3514 being exploited?

CVE-2026-3514 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-3514 affect?

CVE-2026-3514 affects prefect. Severity is high (CVSS 7.5). 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

Q: How urgent is CVE-2026-3514?

Priority 46/100. High severity; Public exploit reference; Remotely exploitable, no login, no user action

This week

HIGH 7.5REMOTEUPGRADE

CVE-2026-3514 is a high-severity flaw (CVSS 7.5) affecting prefect. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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

Why this priority

High severity
Public exploit reference
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.5% (top 59%)
CISA exploited list	No
Weakness	CWE-863
Published	2026-06-02
Last modified	2026-07-22

Publisher (CNA): huntr.dev · Vendor: prefect

Last updated 2026-07-22 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-06-02 09:16 UTCPublished CVE record published
2026-07-22 19:10 UTCUpdated Record last modified

prefect prefect UPGRADE

Affected: < 3.6.22

Fixed in: 3.6.22

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy prefect || rpm -q prefect || prefect --version

2. UPGRADE to 3.6.22 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade prefect

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade prefect

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-3514?

prefect: upgrade to 3.6.22. Exact commands for each OS are on this page.

Is CVE-2026-3514 being exploited?

CVE-2026-3514 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-3514 affect?

CVE-2026-3514 affects prefect. Severity is high (CVSS 7.5). 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

How urgent is CVE-2026-3514?

Priority 46/100. High severity; Public exploit reference; Remotely exploitable, no login, no user action

Related CVEs

CVE-2026-5366 CRITICAL 9.9 DOWNGRADE Prefect version 3.6.23 is vulnerable to remote code execution due to improper handling of user-controlled inpu

References

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