CVE-2026-7723: Prefect Prefect Unauthenticated Event Injection Vulnerability

MODERATE
Advisory Identifier: GHSA-hvph-5985-r63v
Share
CVSS 7.3
CWE-287
Published
Advisory Summary

CVE-2026-7723 is a MODERATE (CVSS 7.3) prefect unauthenticated event injection vulnerability (CWE-287: Improper Authentication) affecting Prefect libraries in the PyPI ecosystem. The issue involves prefect unauthenticated event injection via /api/events/in websocket. Remediation is available by upgrading affected packages to version 3.6.14.

CVE-2026-7723 at a Glance

CVE Identifier CVE-2026-7723
GHSA Identifier GHSA-hvph-5985-r63v
Severity MODERATE
CVSS v3.1 Base Score 7.3
CWE Classification CWE-287: Improper Authentication
Affected Product Prefect
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 7.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability Low (A:L)

How to Fix CVE-2026-7723

To remediate this vulnerability, upgrade all affected Prefect dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

prefect fixed: 3.6.14 
pip install prefect>=3.6.14
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

pip show prefect

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2026-7723, inspect your installed packages using pip:

pip show prefect

Analyze the terminal output to locate any version of Prefect in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.6.14), your application is affected.

Note: The pip show prefect command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-287: Improper Authentication, where when an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. In Prefect, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

A flaw has been found in PrefectHQ prefect up to 3.6.13. Affected is an unknown function of the file /api/events/in of the component WebSocket Endpoint. Executing a manipulation can lead to missing authentication. The attack may be performed from remote. The exploit has been published and may be used. Upgrading to version 3.6.14 is able to address this issue. This patch is called 0d3ab3c2d3f9f98abfafdf7b9f6d4f8ed3925e40. It is recommended to upgrade the affected component.

CVE-2026-7723 Affected Prefect Versions

1 component(s)
Fixed Versions:
3.6.14
Product / Package Ecosystem Affected Versions Fixed Version
prefect
pypi/prefect
PyPI
< 3.6.14
3.6.14

References

NVD — CVE-2026-7723 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-7723
Prefect Source Repository REPOSITORY
https://github.com/PrefectHQ/prefect/pull/20372
Security Fix Commit FIX COMMIT
https://github.com/PrefectHQ/prefect/commit/0d3ab3c2d3f9f98abfafdf7b9f6d4f8ed3925e40
Security Fix Commit FIX COMMIT
https://github.com/PrefectHQ/prefect/commit/f8afecadf88ea5f73694dafa3a365b9d8fae1ad6
Prefect Source Repository REPOSITORY
https://gist.github.com/nedlir/f1ab8aa038aafbcc6beeef21fab1d74f
Prefect Source Repository REPOSITORY
https://github.com/PrefectHQ/prefect
Prefect Release RELEASE
https://github.com/PrefectHQ/prefect/releases/tag/3.6.14
vuldb.com/submit/807256 WEB
https://vuldb.com/submit/807256
vuldb.com/vuln/360899 WEB
https://vuldb.com/vuln/360899
vuldb.com/vuln/360899/cti WEB
https://vuldb.com/vuln/360899/cti

Frequently Asked Questions

What is CVE-2026-7723?
CVE-2026-7723 is a security vulnerability in Prefect involving Prefect Unauthenticated Event Injection via /api/events/in WebSocket under CWE-287: Improper Authentication.
Which Prefect versions are affected?
Affected versions include releases prior to 3.6.14 across affected packages: prefect.
What version fixes CVE-2026-7723?
Upgrading to 3.6.14 (or the latest patched release for your respective branch) resolves the vulnerability.
Is prefect affected?
Yes, prefect is affected in releases prior to 3.6.14. Upgrade your dependency to 3.6.14 or later.
What is the CVSS score of CVE-2026-7723?
CVE-2026-7723 has a CVSS v3.1 base score of 7.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.
What CWE is associated with CVE-2026-7723?
CVE-2026-7723 is classified under CWE-287: Improper Authentication (When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.).
How can I check PyPI dependencies for CVE-2026-7723?
Run the dependency tree command: 'pip show prefect'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-hvph-5985-r63v",
  "modified" : "2026-05-22T13:06:48Z",
  "published" : "2026-05-04T03:31:28Z",
  "aliases" : [ "CVE-2026-7723" ],
  "summary" : "Prefect Unauthenticated Event Injection via /api/events/in WebSocket",
  "details" : "A flaw has been found in PrefectHQ prefect up to 3.6.13. Affected is an unknown function of the file /api/events/in of the component WebSocket Endpoint. Executing a manipulation can lead to missing authentication. The attack may be performed from remote. The exploit has been published and may be used. Upgrading to version 3.6.14 is able to address this issue. This patch is called 0d3ab3c2d3f9f98abfafdf7b9f6d4f8ed3925e40. It is recommended to upgrade the affected component.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "prefect"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "3.6.14"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-7723"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/PrefectHQ/prefect/pull/20372"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/PrefectHQ/prefect/commit/0d3ab3c2d3f9f98abfafdf7b9f6d4f8ed3925e40"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/PrefectHQ/prefect/commit/f8afecadf88ea5f73694dafa3a365b9d8fae1ad6"
  }, {
    "type" : "WEB",
    "url" : "https://gist.github.com/nedlir/f1ab8aa038aafbcc6beeef21fab1d74f"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/PrefectHQ/prefect"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/PrefectHQ/prefect/releases/tag/3.6.14"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/submit/807256"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/vuln/360899"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/vuln/360899/cti"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-287" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-22T13:06:48Z",
    "nvd_published_at" : "2026-05-04T03:16:13Z"
  }
}