CVE-2025-8943
CriticalExploitedPublic exploitFlowise OS command remote code execution
Published Aug 14, 2025 · Updated Oct 8, 2026 · Also known as GHSA-2vv2-3x8x-4gv7
Key Facts
Patch immediately- CVE-2025-8943 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Flowise (Flowiseai).
- It is exploited in the wild, listed in Industry KEV feed, CIRCL KEV since Nov 27, 2025. Public exploit code is available.
- EPSS estimates a 75% probability of exploitation in the next 30 days.
- Fixed versions are available, including Flowise 3.0.1.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
75%
Higher than 99.5% of all scored CVEs
Exploited in the wild
Yes
2 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
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Description
The Custom MCPs feature is designed to execute OS commands, for instance, using tools like npx to spin up local MCP Servers. However, Flowise's inherent authentication and authorization model is minimal and lacks role-based access controls (RBAC). Furthermore, in Flowise versions before 3.0.1 the default installation operates without authentication unless explicitly configured. This combination allows unauthenticated network attackers to execute unsandboxed OS commands.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Nov 27, 2025 | n/a | Not reported |
| CIRCL KEV | Aug 5, 2026 | n/a | Not reported |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
3 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| FlowiseFlowiseai | See advisory | 3.0.1 |
Patched Releases
Flowise
3.0.1
Timeline
Publicly disclosed
Aug 14, 2025
Added to Industry KEV feed
Nov 27, 2025
Added to CIRCL KEV
Aug 5, 2026
Last updated
Oct 8, 2026
Weakness Type
- CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
- CWE-306 Missing Authentication for Critical Function
- CWE-862 Missing Authorization
References
- advisoryGHSA advisory
- advisoryhttps://github.com/CVEProject/cvelistV5/tree/main/cves/2025/8xxx/CVE-2025-8943.json
- advisoryhttps://nvd.nist.gov/vuln/detail/CVE-2025-8943
- exploitVulnCheck exploitation report
- exploitMSF flowise_custommcp_rce.rb
FAQ
Common Questions.
The Custom MCPs feature is designed to execute OS commands, for instance, using tools like npx to spin up local MCP Servers.
Affected: Flowise (Flowiseai). The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed, CIRCL KEV since Nov 27, 2025.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including Flowise 3.0.1.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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