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CVE-2026-87011

7.5 HIGHPublic exploitEPSS 0.34%
  1. Published9 Sept 2026

Description

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.0 until 0.11.1, the unauthenticated POST /oauth/backchannel-logout handler in backend/open_webui/utils/oauth.py fetched the OIDC discovery document and signing keys before validating a submitted logout token. Each request repeated uncached network fetches, and the signing-key lookup blocked the async event loop, so requests carrying invalid tokens could stall the single-worker instance and amplify traffic to the identity provider when ENABLE_OAUTH_BACKCHANNEL_LOGOUT was enabled. This issue is fixed in version 0.11.1.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeUnchanged
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

Openwebui Open Webui≥ 0.9.0 < 0.11.1

Remediation

Fixed in
Openwebui Open Webui≥ 0.11.1

References

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Frequently asked

Is CVE-2026-87011 being actively exploited?

CVE-2026-87011 is not in the CISA KEV catalog. A public exploit reference exists, so treat it as exploitable. Its EPSS exploit probability is 0.34%.

How severe is CVE-2026-87011?

CVE-2026-87011 has a CVSS 3.1 base score of 7.5, rated high. EPSS estimates a 0.34% probability of exploitation.

Which products are affected by CVE-2026-87011?

Affected products include Openwebui Open Webui.

How do I fix CVE-2026-87011?

Upgrade affected software to a fixed version, for example Openwebui Open Webui 0.11.1 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-87011 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.