CVE-2026-88002Public exploitNetwork attack vector

Authenticated server denial of service via cyclic history

Published Sep 9, 2026 · Updated Sep 9, 2026

Infinite-loop denial of service in Open WebUI 0.5.0 through 0.11.0 allows remote authenticated users to hang or terminate the server. The message-chain helper in backend/open_webui/utils/misc.py follows parent map keys but records each message body's optional id, so id-less parent cycles never satisfy the exit check. A default-role account can persist such a cycle; one reconstruction blocks all requests, consumes memory until termination, and remains triggerable after restart.

CVSS severity6.5
Medium
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Infinite-loop denial of service in Open WebUI 0.5.0 through 0.11.0 allows remote authenticated users to hang or terminate the server. The message-chain helper in backend/open_webui/utils/misc.py follows parent map keys but records each message body's optional id, so id-less parent cycles never satisfy the exit check. A default-role account can persist such a cycle; one reconstruction blocks all requests, consumes memory until termination, and remains triggerable after restart.

The record

CVE
CVE-2026-88002
Published
Sep 9, 2026
Updated
Sep 9, 2026
Vendor
Open WebUI
Product
Open WebUI
Classifications
CWE-835, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 9, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 9, 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.

  1. Affected versionversion=>= 0.5.0, < 0.11.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Open WebUI · Open WebUIversion=>= 0.5.0, < 0.11.1

Published CVSS scores

6.5GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-835Loop with Unreachable Exit Condition ('Infinite Loop')
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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