CVE-2026-56400

CRITICALNVD 9.69.6—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.6 under NVD CVSS v3. EPSS exploit probability: 0.3%, top 73% of all CVEs by exploit prediction. GitHub Security Advisory enrichment pending alignment with NVD CVSS.

Triggered by: NVD CVSS baseline
Sources: epss, ghsa, nvd
Trending — 3 sources updated this weekElevated
9.6EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.6Exploit: Elevated riskExposed: 0

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

open-webui before 0.3.14 contains a cross-origin resource sharing misconfiguration allowing arbitrary origins with allow_origins=* and authenticated requests to the /api/v1/functions endpoint. Attackers can execute arbitrary code on the openwebui instance by crafting malicious cross-site requests from attacker-controlled websites when an admin user visits them.

CVSS v3
9.6
EG Score
9.6(medium)
EG Risk
59(Track*)
EG Risk 59/100SSVC: 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
Severity96% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Watch closely — could escalate to Attend.
EPSS PROB
0%
EPSS %ILE
27%
KEV
Not listed

Published

July 15, 2026

Last Modified

July 16, 2026

Advisory Details (2)

Auto-updated Jul 15, 2026
🔬 Proof of concept available. Patch available. Sources: github.
generic

open-webui - Remote Code Execution via CORS Misconfiguration and Session Validation | Advisories | VulnCheck

https://www.vulncheck.com/advisories/open-webui-remote-code-execution-via-cors-misconfiguration-and-session-validation
github Patch Available🟡 PoC Available

GitHub Security Lab (GHSL) Vulnerability Report, open-webui: GHSL-2024-174, GHSL-2024-175 · Advisory · open-webui/open-webui · GitHub

https://github.com/open-webui/open-webui/security/advisories/GHSA-6xcp-7mpr-m7wm

Vendor Advisories for CVE-2026-56400(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-webui0.1.124 ... 0.3.9 (51 versions)0.3.33—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 16× in last 7d / 27× 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. 2026-07-27 08:01 UTCGHSA enrichment
  2. 2026-07-27 03:57 UTCGHSA enrichment
  3. 2026-07-26 23:52 UTCGHSA enrichment
  4. 2026-07-26 19:46 UTCGHSA enrichment
  5. 2026-07-26 15:42 UTCEG score recompute
  6. 2026-07-26 15:42 UTCGHSA enrichment
  7. 2026-07-26 14:54 UTCEPSS rescore
  8. 2026-07-26 11:38 UTCEG score recompute
  9. 2026-07-26 11:38 UTCGHSA enrichment
  10. 2026-07-25 14:18 UTCEPSS rescore
  11. 2026-07-24 14:18 UTCEPSS rescore
  12. 2026-07-23 14:18 UTCEPSS rescore
  13. 2026-07-23 03:20 UTCEG score recompute▲ 1.30
  14. 2026-07-22 14:08 UTCEPSS rescore
  15. 2026-07-21 15:25 UTCEPSS rescore
  16. 2026-07-20 17:08 UTCEPSS rescore
  17. 2026-07-19 14:31 UTCEPSS rescore
  18. 2026-07-19 14:31 UTCEPSS rescore
  19. 2026-07-19 02:29 UTCEPSS rescore
  20. 2026-07-18 10:04 UTCEPSS rescore
  21. 2026-07-17 03:02 UTCGHSA enrichment
  22. 2026-07-16 20:23 UTCNVD updateCVSS v3 → 9.6 · severity → CRITICAL
  23. 2026-07-16 17:03 UTCEPSS rescore
  24. 2026-07-16 14:00 UTCGHSA enrichment
  25. 2026-07-16 00:57 UTCGHSA enrichment
Show 2 more
  1. 2026-07-15 11:55 UTCEG score recompute
  2. 2026-07-15 11:54 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-56400?
CVE-2026-56400 is a critical vulnerability published on July 15, 2026. open-webui before 0.3.14 contains a cross-origin resource sharing misconfiguration allowing arbitrary origins with allow_origins=* and authenticated requests to the /api/v1/functions endpoint. Attackers can execute arbitrary code on the openwebui instance by crafting malicious cross-site requests…
When was CVE-2026-56400 disclosed?
CVE-2026-56400 was first published in the National Vulnerability Database on July 15, 2026, with the most recent update on July 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-56400 actively exploited?
CVE-2026-56400 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 72.7% of all scored CVEs.
What is the CVSS score of CVE-2026-56400?
CVE-2026-56400 has a CVSS v3 base score of 9.6 (NVD).
How do I remediate CVE-2026-56400?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-56400, 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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