Unauthenticated event injection via WebSocket bypass
Published May 4, 2026 · Updated May 4, 2026
Missing authentication in Prefect 3.6.0 through 3.6.13 allows remote attackers to inject events through the /api/events/in WebSocket. The stream_events_in handler accepts the socket directly instead of invoking accept_prefect_socket, so configured API authentication never validates the connection. Exposure requires a network-reachable self-hosted server with API authentication configured; injected records can pollute event history or trigger matching automations.
Summary
What happened
Missing authentication in Prefect 3.6.0 through 3.6.13 allows remote attackers to inject events through the /api/events/in WebSocket. The stream_events_in handler accepts the socket directly instead of invoking accept_prefect_socket, so configured API authentication never validates the connection. Exposure requires a network-reachable self-hosted server with API authentication configured; injected records can pollute event history or trigger matching automations.
The record
- CVE
- CVE-2026-7723
- Published
- May 4, 2026
- Updated
- May 4, 2026
- Vendor
- Prefect Technologies, Inc.
- Product
- Prefect
- Classifications
- CWE-287, CWE-306, T1565.001, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 4, 2026CVE publishedPublication date reported by the CVE source.
- May 4, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=3.6.0
- Affected versionversion=3.6.1
- Affected versionversion=3.6.10
- Affected versionversion=3.6.11
- Affected versionversion=3.6.12
- Affected versionversion=3.6.13
- Affected versionversion=3.6.2
- Affected versionversion=3.6.3
- Affected versionversion=3.6.4
- Affected versionversion=3.6.5
- Affected versionversion=3.6.6
- Affected versionversion=3.6.7
- Affected versionversion=3.6.8
- Affected versionversion=3.6.9
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Prefect unauthenticated event injection proof of conceptfunctional · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
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