What is CVE-2026-87999?
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. Prior to 0.11.1, POST /api/v1/retrieval/process/web and POST /api/v1/retrieval/process/web/search in backend/open_webui/retrieval/web/utils.py treated Python's globally routable address classification as proof that a destination was external. An authenticated user could make an Azure-hosted instance fetch and return content from 168.63.129.16, the Azure platform channel, as well as other reserved ranges that the standard classification did not reject. This issue is fixed in version 0.11.1.
The record classifies CVE-2026-87999 under weakness class CWE-918. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs low-privilege credentials, needs no user interaction, and has high impact on confidentiality. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 26 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 7.1 — HIGH
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N - EPSS (FIRST)
- 0.2% probability of exploitation in the next 30 days, higher than 12.1% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 4/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-09-09, last modified 2026-09-10
Is CVE-2026-87999 being exploited?
It currently carries a trending score of 33 in the Threadlinqs vulnerability feed.
Affected products and versions
- open-webui: open-webui
Affected software packages:
pip:open-webui— patched in 0.11.1
How to fix CVE-2026-87999
Fixed versions are recorded for 1 package: pip:open-webui 0.11.1. No vendor patch reference has been recorded for CVE-2026-87999 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2026-87999
No threat campaign in the Threadlinqs corpus currently references CVE-2026-87999, in its CVE list or as an indicator. The linkage is recomputed from the live corpus on every daily ingest, so this section fills in as soon as a tracked campaign cites the identifier.
Sources
Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on . This product uses the NVD API but is not endorsed or certified by the NVD.