CVE-2026-45396Public exploitNetwork attack vector

Feedback identity spoofing via unsafe dictionary merge

Published May 15, 2026 · Updated May 15, 2026

Mass assignment in Open WebUI before 0.9.5 allows remote authenticated users to spoof feedback authors and manipulate model ratings. FeedbackForm preserves arbitrary extra fields, and insert_new_feedback() merges them after server-derived values, allowing supplied user_id, id, and version fields to overwrite protected attributes. Any authenticated account can create falsely attributed feedback and distort stored Elo evaluation data; no confidentiality impact is reported.

CVSS severity5.4
Medium
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Mass assignment in Open WebUI before 0.9.5 allows remote authenticated users to spoof feedback authors and manipulate model ratings. FeedbackForm preserves arbitrary extra fields, and insert_new_feedback() merges them after server-derived values, allowing supplied user_id, id, and version fields to overwrite protected attributes. Any authenticated account can create falsely attributed feedback and distort stored Elo evaluation data; no confidentiality impact is reported.

The record

CVE
CVE-2026-45396
Published
May 15, 2026
Updated
May 15, 2026
Vendor
Open WebUI
Product
Open WebUI
Classifications
CWE-915, T1565.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 15, 2026CVE publishedPublication date reported by the CVE source.
  2. May 15, 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=< 0.9.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Open WebUI · Open WebUIversion=< 0.9.5

Published CVSS scores

5.4GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L

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-915Improperly Controlled Modification of Dynamically-Determined Object Attributes
T1565.001Stored Data Manipulation

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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