NVD / CVE Program· CNA GitHub_M

CVE-2026-88000: Open WebUI: Any authenticated user can hang the server via message deletion in a cyclic chat tree

MediumCVSS 6.5 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 26/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.59% (FIRST EPSS).
Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
Fixed version: open-webui open-webui 0.11.1.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to open-webui open-webui 0.11.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.10.0 until 0.11.1, DELETE /api/v1/chats/{id}/messages/{message_id} used the chat-history deletion helper in backend/open_webui/models/chats.py to follow childrenIds without recording visited message identifiers. An authenticated user could store a cyclic chat tree and delete a message, causing a synchronous infinite loop on the server request loop that blocked every user's requests until the process was killed. This issue is fixed in version 0.11.1.

Denial of service

Published: Sep 9, 2026
Updated: Sep 14, 2026
EPSS: 0.5% · 48th percentile
CWE: CWE-835

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 26 / 40 · 6.5 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.5%

CISA SSVC decision

Exploitation: proof of concept
Automatable: no
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · GitHub_M: 6.5; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
openwebui	open webui	cpe:2.3:a:openwebui:open_webui

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

open-webui open-webui
- >= 0.10.0, < 0.11.1affected

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

openwebui open webui0.10.0 and later · before 0.11.1

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
PyPI	open-webui	from 0.10.0 · before 0.11.1	0.11.1

Same product

openwebui: all records

Other highest-scoring records for the same primary product.

CVE-2026-44566Open WebUI: Arbitrary File Upload and Path Traversal
39Monitor
CVE-2026-56400open-webui - Remote Code Execution via CORS Misconfiguration and Session Validation
36Monitor
CVE-2026-59216Open WebUI: Cross-user code-interpreter and tool execution via unvalidated Socket.IO event-caller session_id
36Monitor

Published before and after this one in the same product

← EarlierCVE-2026-87998Sep 9, 2026 · Open WebUI: Non-admin users can delete admin-owned external knowledge connections via knowledge base deletion
28Monitor
← EarlierCVE-2026-87999Sep 9, 2026 · Open WebUI: Any authenticated user can reach the Azure platform channel via server-side web fetch
28Monitor
Later →CVE-2026-88001Sep 9, 2026 · Open WebUI: Server-side fetches reach blocked and internal hosts via unvalidated HTTP redirect targets
20Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
open-webui open-webui	0.11.1 · description	Vendor (CNA)
PyPI:open-webui	0.11.1	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

open-webui/open-webuicommit b933292

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

CVE-2026-880020 days apartOpen WebUI: Any authenticated user can hang the server via a cyclic chat message history
26Monitor
CVE-2026-870130 days apartOpen WebUI: Any authenticated user can start a non-terminating request via a folder parent cycle
17Monitor