CVE-2026-44558Public exploitNetwork attack vector

Authenticated channel exposure via unfiltered access grants

Published May 15, 2026 · Updated May 15, 2026

Authorization bypass in Open WebUI before 0.9.0 allows remote authenticated users to expose group channels through crafted grants. The channel creation and update paths pass submitted access grants directly to set_access_grants without calling filter_allowed_access_grants. Exploitation requires group-channel creation rights or channel ownership and a restrictive sharing policy; wildcard or individual grants then defeat that policy.

CVSS severity5.4
Medium
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authorization bypass in Open WebUI before 0.9.0 allows remote authenticated users to expose group channels through crafted grants. The channel creation and update paths pass submitted access grants directly to set_access_grants without calling filter_allowed_access_grants. Exploitation requires group-channel creation rights or channel ownership and a restrictive sharing policy; wildcard or individual grants then defeat that policy.

The record

CVE
CVE-2026-44558
Published
May 15, 2026
Updated
May 15, 2026
Vendor
Open WebUI
Product
Open WebUI
Classifications
CWE-862
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=< 0.9.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Open WebUI · Open WebUIversion=< 0.9.0

Published CVSS scores

5.4GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-862Missing Authorization

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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