CVE-2025-59528

CRITICALNVD 10.010.0—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 10.0 under NVD CVSS v3. EPSS exploit probability: 90.2%, top 0% 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, nvd
Weaponized
10.0EG
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 90%
  • Public exploit code is available (Metasploit, ssvc poc, epss top5pct, epss high, public exploit)
CISA-KEV: Not listedEPSS PROB: 90%CVSS: 10.0Exploit: Metasploit · ssvc poc · epss top5pct · epss high · public exploitExposed: 0

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

Flowise is a drag & drop user interface to build a customized large language model flow. In version 3.0.5, Flowise is vulnerable to remote code execution. The CustomMCP node allows users to input configuration settings for connecting to an external MCP server. This node parses the user-provided mcpServerConfig string to build the MCP server configuration. However, during this process, it executes JavaScript code without any security validation. Specifically, inside the convertToValidJSONString function, user input is directly passed to the Function() constructor, which evaluates and executes the input as JavaScript code. Since this runs with full Node.js runtime privileges, it can access dangerous modules such as child_process and fs. This issue has been patched in version 3.0.6.

CVSS v3
10.0
EG Score
10.0(medium)
EG Risk
96(Attend)
EG Risk 96/100SSVC: Attend

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
Severity100% × 45%
Exploitation90% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
90%
EPSS %ILE
100%
KEV
Not listed

Published

September 22, 2025

Last Modified

September 23, 2025

Advisory Details (8)

Auto-updated Aug 8, 2026
🔬 Proof of concept available. Patch available. Sources: github_release, github.
github Patch Available🟡 PoC Available

RCE in FlowiseAI/Flowise · Advisory · FlowiseAI/Flowise · GitHub

https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-3gcm-f6qx-ff7p
github_release Patch Available

[email protected]

Patch available: FlowiseAI/Flowise [email protected]

https://github.com/FlowiseAI/Flowise/releases/tag/flowise%403.0.6
generic

Flowise/packages/server/src/services/nodes/index.ts at 5930f1119c655bcf8d2200ae827a1f5b9fec81d0 · FlowiseAI/Flowise · GitHub

https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/server/src/services/nodes/index.ts#L91-L94
generic

Flowise/packages/server/src/routes/node-load-methods/index.ts at 5930f1119c655bcf8d2200ae827a1f5b9fec81d0 · FlowiseAI/Flowise · GitHub

https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/server/src/routes/node-load-methods/index.ts#L5
generic

Flowise/packages/server/src/controllers/nodes/index.ts at 5930f1119c655bcf8d2200ae827a1f5b9fec81d0 · FlowiseAI/Flowise · GitHub

https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/server/src/controllers/nodes/index.ts#L57-L78
generic

Flowise/packages/components/nodes/tools/MCP/CustomMCP/CustomMCP.ts at 5930f1119c655bcf8d2200ae827a1f5b9fec81d0 · FlowiseAI/Flowise · GitHub

https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/components/nodes/tools/MCP/CustomMCP/CustomMCP.ts#L262-L270
generic

Flowise/packages/components/nodes/tools/MCP/CustomMCP/CustomMCP.ts at 5930f1119c655bcf8d2200ae827a1f5b9fec81d0 · FlowiseAI/Flowise · GitHub

https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/components/nodes/tools/MCP/CustomMCP/CustomMCP.ts#L220
generic

Flowise/packages/components/nodes/tools/MCP/CustomMCP/CustomMCP.ts at 5930f1119c655bcf8d2200ae827a1f5b9fec81d0 · FlowiseAI/Flowise · GitHub

https://github.com/FlowiseAI/Flowise/blob/5930f1119c655bcf8d2200ae827a1f5b9fec81d0/packages/components/nodes/tools/MCP/CustomMCP/CustomMCP.ts#L132

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
flowise3.0.53.0.6—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 3× in last 7d / 12× 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. 2026-08-04 15:09 UTCEPSS rescore
  2. 2026-08-04 15:09 UTCEPSS rescore
  3. 2026-08-03 10:35 UTCEPSS rescore
  4. 2026-08-01 04:15 UTCEPSS rescore
  5. 2026-07-28 15:35 UTCEPSS rescore
  6. 2026-07-24 14:17 UTCEPSS rescore
  7. 2026-07-23 19:41 UTCOSV refresh
  8. 2026-07-23 03:00 UTCEG score recompute
  9. 2026-07-22 14:08 UTCEPSS rescore
  10. 2026-07-22 14:07 UTCEPSS rescore
  11. 2026-07-15 16:57 UTCEPSS rescore
  12. 2026-07-15 16:57 UTCEPSS rescore
  13. 2026-07-06 13:41 UTCOSV refresh
  14. 2026-07-02 17:01 UTCEPSS rescore
  15. 2026-06-25 13:49 UTCEPSS rescore
  16. 2026-06-24 14:04 UTCEPSS rescore
  17. 2026-06-24 14:04 UTCEPSS rescore
  18. 2026-06-23 21:32 UTCEPSS rescore
  19. 2026-06-18 17:52 UTCEPSS rescore
  20. 2026-06-18 17:52 UTCEPSS rescore
  21. 2026-06-18 02:05 UTCOSV refresh
  22. 2026-06-16 17:52 UTCEPSS rescore
  23. 2026-06-16 17:52 UTCEPSS rescore
  24. 2026-06-15 17:48 UTCEPSS rescore
  25. 2026-06-14 23:17 UTCEPSS rescore
Show 20 more
  1. 2026-06-13 23:00 UTCEPSS rescore
  2. 2026-06-12 23:11 UTCEPSS rescore
  3. 2026-06-10 22:18 UTCEPSS rescore
  4. 2026-06-10 22:18 UTCEPSS rescore
  5. 2026-06-10 13:22 UTCEPSS rescore
  6. 2026-06-10 13:22 UTCEPSS rescore
  7. 2026-06-08 14:16 UTCEPSS rescore
  8. 2026-06-08 14:16 UTCEPSS rescore
  9. 2026-06-07 15:24 UTCEPSS rescore
  10. 2026-06-07 15:24 UTCEPSS rescore
  11. 2026-06-06 13:47 UTCEPSS rescore
  12. 2026-06-06 13:47 UTCEPSS rescore
  13. 2026-06-05 22:46 UTCEPSS rescore
  14. 2026-06-05 22:46 UTCEPSS rescore
  15. 2026-06-02 20:12 UTCEPSS rescore
  16. 2026-06-02 20:12 UTCEPSS rescore
  17. 2026-05-31 22:30 UTCEPSS rescore
  18. 2026-05-31 22:30 UTCEPSS rescore
  19. 2026-05-29 22:11 UTCEG score recompute
  20. 2026-05-29 13:44 UTCEPSS rescore

Publicly available exploits

(3 references)

Working exploit code is in the public domain (1 Metasploit module) (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • Exploit-DBEDB-52440
    First seen Oct 31, 2025

    Flowise 3.0.4 - Remote Code Execution (RCE)

    Open source ↗
  • Metasploitexploit/multi/http/flowise_js_rce✓ verified
    First seen Sep 13, 2025

    Flowise JS Injection RCE

    Open source ↗
  • Nucleihttp/cves/2025/CVE-2025-59528.yaml
    First seen Jan 1, 2025

    Flowise - Remote Code Execution

    Open source ↗

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2025-59528?
CVE-2025-59528 is a critical vulnerability published on September 22, 2025. Flowise is a drag & drop user interface to build a customized large language model flow. In version 3.0.5, Flowise is vulnerable to remote code execution. The CustomMCP node allows users to input configuration settings for connecting to an external MCP server. This node parses the user-provided…
When was CVE-2025-59528 disclosed?
CVE-2025-59528 was first published in the National Vulnerability Database on September 22, 2025, with the most recent update on September 23, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2025-59528 actively exploited?
CVE-2025-59528 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 90% probability of exploitation in the next 30 days, which ranks it in the top 0.2% of all scored CVEs.
What is the CVSS score of CVE-2025-59528?
CVE-2025-59528 has a CVSS v3 base score of 10.0 (NVD).
How do I remediate CVE-2025-59528?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2025-59528, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2025-59528

Explore →

Is Your Infrastructure Affected by CVE-2025-59528?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs