CVE-2026-87998

HIGHPre-NVD 7.17.1—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 80% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
7.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.1Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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/knowledge/{id}/delete in backend/open_webui/routers/knowledge.py authorized deletion against the knowledge base but then removed its administrator-owned external connection without a separate administrator check or a check for other dependent knowledge bases. A non-administrator with write access to one external knowledge base could delete shared instance configuration and make every other knowledge base using that connection unavailable. This issue is fixed in version 0.11.1.

CVSS v3
7.1
EG Score
7.1(medium)
EG Risk
32(Track)
EG Risk 32/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity71% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
20%
KEV
Not listed

Published

September 9, 2026

Last Modified

September 16, 2026

Advisory Details (4)

Auto-updated Sep 9, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_pr, github_commit, github_release.
github_release Patch Available

v0.11.1

Patch available: open-webui/open-webui v0.11.1

https://github.com/open-webui/open-webui/releases/tag/v0.11.1
github_commit

commit dc03e7e595d6 (open-webui/open-webui)

Fix landed in open-webui/open-webui commit dc03e7e595d6 — awaiting tagged release

https://github.com/open-webui/open-webui/commit/dc03e7e595d61be97b25a1dd7bb99ad264f73199
github_pr

refac: keep external connections until their last knowledge base is removed

Fix merged in open-webui/open-webui PR #28113 on 2026-08-24 — awaiting tagged release

https://github.com/open-webui/open-webui/pull/28113
github Patch Available🟡 PoC Available

Non-admin users can delete admin-owned external knowledge connections via knowledge base deletion · Advisory · open-webui/open-webui · GitHub

Affected: 0.11.1 by

https://github.com/open-webui/open-webui/security/advisories/GHSA-2724-6cpj-gf3v

Vendor Advisories for CVE-2026-87998(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
PyPI(1)
PackageVulnerable rangeFixed inDependents
open-webui0.10.0, 0.10.1, 0.10.2, 0.11.00.11.1—

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 14× in last 7d / 22× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-19 04:23 UTCEG score recompute
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 04:03 UTCEG score recompute
  4. 2026-09-17 19:32 UTCEPSS rescore
  5. 2026-09-16 15:30 UTCEG score recompute
  6. 2026-09-16 14:09 UTCEPSS rescore
  7. 2026-09-16 08:54 UTCEG score recompute
  8. 2026-09-16 05:15 UTCEPSS rescore
  9. 2026-09-15 07:59 UTCEG score recompute
  10. 2026-09-15 03:12 UTCEPSS rescore
  11. 2026-09-13 19:26 UTCEG score recompute
  12. 2026-09-13 16:48 UTCEPSS rescore
  13. 2026-09-12 19:05 UTCEG score recompute
  14. 2026-09-12 15:02 UTCEPSS rescore
  15. 2026-09-11 18:44 UTCEG score recompute
  16. 2026-09-11 14:53 UTCEPSS rescore
  17. 2026-09-11 14:53 UTCEPSS rescore
  18. 2026-09-10 18:23 UTCEG score recompute
  19. 2026-09-10 17:50 UTCEG score recompute
  20. 2026-09-09 22:31 UTCEG score recompute
  21. 2026-09-09 21:41 UTCEG score recompute
  22. 2026-09-09 21:40 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-87998?
CVE-2026-87998 is a high vulnerability published on September 9, 2026. 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/knowledge/{id}/delete in backend/open_webui/routers/knowledge.py authorized deletion against the knowledge base but then removed its administrator-owned external connection…
When was CVE-2026-87998 disclosed?
CVE-2026-87998 was first published in the National Vulnerability Database on September 9, 2026, with the most recent update on September 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-87998 actively exploited?
CVE-2026-87998 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 80.2% of all scored CVEs.
What is the CVSS score of CVE-2026-87998?
CVE-2026-87998 has a CVSS v3 base score of 7.1 (NVD).
How do I remediate CVE-2026-87998?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-87998, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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