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TI-2026-23650 Aliases CVE-2026-30821GHSA-j8g8-j7fc-43v6

Flowise: Arbitrary File Upload via MIME Spoofing

Priority HIGH 69CWE-434Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Attack requirements
Present
Impact type
Code execution
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-434.

Summary

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to version 3.0.13, the /api/v1/attachments/:chatflowId/:chatId endpoint is listed in WHITELIST_URLS, allowing unauthenticated access to the file upload API. While the server validates uploads based on the MIME types defined in chatbotConfig.fullFileUpload.allowedUploadFileTypes, it implicitly trusts the client-provided Content-Type header (file.mimetype) without verifying the file's actual content (magic bytes) or extension (file.originalname). Consequently, an attacker can bypass this restriction by spoofing the Content-Type as a permitted type (e.g., application/pdf) while uploading malicious scripts or arbitrary files. Once uploaded via addArrayFilesToStorage, these files persist in backend storage (S3, GCS, or local disk). This vulnerability serves as a critical entry point that, when chained with other features like static hosting or file retrieval, can lead to Stored XSS, malicious file hosting, or Remote Code Execution (RCE). This issue has been patched in version 3.0.13.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.16712 97th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed Flowise (FlowiseAI): 3.0.13flowise (npm): 3.0.13

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
FlowiseAIFlowisebefore 3.0.133.0.13Patch availableCNA
—flowise (npm)before 3.0.133.0.13Patch availableGHSA-j8g8-j7fc-43v6
  • Flowise VendorFlowiseAI Affected before 3.0.13 Fixed in 3.0.13 Patch available CNA
  • flowise (npm) Vendor— Affected before 3.0.13 Fixed in 3.0.13 Patch available GHSA-j8g8-j7fc-43v6

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:flowiseai:flowise:*:*:*:*:*:*:*:*before 3.0.13VulnerableFlowiseAI
  • cpe:2.3:a:flowiseai:flowise:*:*:*:*:*:*:*:* Versions before 3.0.13 Vulnerable ·FlowiseAI

Remediation

  • Fix · CNA Flowise (FlowiseAI) Fixed in 3.0.13
  • Fix · GHSA-j8g8-j7fc-43v6 flowise (npm) Fixed in 3.0.13 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-30821
  2. 2026-10-03 Alias added: GHSA-j8g8-j7fc-43v6
  3. 2026-10-25 EPSS moved to the 95th–99th percentile

References

Exploit 1

Advisory 1

Other 2

  • TI-2025-37059 Flowise has Remote Code Execution vulnerability CVSS 3.1CRITICAL 10.0
  • TI-2025-36193 Flowise Cloud and Local Deployments have Unauthenticated Password Reset Token Disclosure that Leads to Account Takeover CVSS 3.1CRITICAL 9.8
  • TI-2025-08190 Unsupervised OS command execution leads to remote code execution by unauthenticated network attackers CVSS 3.1CRITICAL 9.8
  • TI-2026-51595 Flowise before 3.1.3 Sandbox Escape via Puppeteer CVSS 4.0CRITICAL 9.4
  • TI-2026-49250 Flowise: CSV Agent Prompt Injection Remote Code Execution Vulnerability CVSS 4.0CRITICAL 9.5
  • TI-2025-43459 Flowise through 2.2.7 - Arbitrary File Write to Remote Code Execution via document-store API CVSS 4.0CRITICAL 10.0
See all 127 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences