Flowise CVE-2026-12821

Q: What is the CVSS score of CVE-2026-12821?

CVE-2026-12821 has a CVSS 4.0 base score of 2.1 (Low). CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.3%.

EUVD-2026-38202 LOW

Path Traversal (CWE-22)

2026-06-21 VulDB

GHSA-67qj-p3v2-73g7

Path Traversal Flowise

2.1

CVSS 4.0 · Vendor: VulDB

Severity by source

Vendor (VulDB) PRIMARY

2.1 MEDIUM

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

vuln.today AI

6.3 MEDIUM

Network-reachable path traversal requiring low-privilege auth; limited C/I/A impact with no scope change beyond the vulnerable system.

3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N

Primary rating from Vendor (VulDB).

CVSS VectorVendor: VulDB

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Lifecycle Timeline

Analysis Generated

Jun 22, 2026 - 06:49 vuln.today

Severity Changed

Jun 22, 2026 - 00:22 NVD

MEDIUM LOW

CVSS changed

Jun 22, 2026 - 00:22 NVD

5.3 (MEDIUM) 2.1 (LOW)

DescriptionCVE.org

A vulnerability was determined in FlowiseAI Flowise up to 3.1.2. The impacted element is an unknown function of the file packages/components/nodes/documentloaders/S3/S3.ts of the component S3 Document Loader. Executing a manipulation can lead to path traversal. It is possible to launch the attack remotely. The vendor was contacted early about this disclosure but did not respond in any way.

AnalysisAI

Path traversal in FlowiseAI Flowise's S3 Document Loader component (packages/components/nodes/documentloaders/S3/S3.ts) enables authenticated remote attackers to manipulate S3 object key inputs to access files outside the intended storage scope. Versions 3.1.0 through 3.1.2 are confirmed affected. Publicly available exploit code exists (E:P in the CVSS 4.0 vector), and the vendor did not respond to responsible disclosure, leaving no vendor-confirmed patch at time of analysis.

Technical ContextAI

Flowise is an open-source LLM workflow orchestration platform built on Node.js. The vulnerable component is the S3 Document Loader node, responsible for fetching documents from AWS S3 buckets during workflow execution. The CPE string cpe:2.3:a:flowiseai:flowise:*:*:*:*:*:*:*:* identifies the FlowiseAI Flowise application as the affected software. CWE-22 (Improper Limitation of a Pathname to a Restricted Directory - Path Traversal) indicates the TypeScript file S3.ts fails to sanitize or validate the S3 object key parameter before using it in path construction, allowing traversal sequences to resolve to unintended paths within the bucket or underlying file system context.

RemediationAI

No vendor-released patch has been identified at time of analysis - the vendor did not respond to responsible disclosure, and no fixed version is confirmed in available data. As a compensating control, restrict access to the S3 Document Loader node within Flowise to only trusted users or disable the node entirely if S3 loading is not operationally required (note: disabling the node removes S3-based document ingestion capability). Enforce AWS IAM least-privilege principles on any credentials configured in Flowise: scope the IAM policy to only specific S3 bucket prefixes or object key patterns required for legitimate workflows, which limits the blast radius of any traversal. Enable AWS S3 server-side access logging and set up CloudTrail alerts for anomalous object key patterns (e.g., keys containing ../ sequences). Monitor the GitHub PoC at https://github.com/dxz0069/softwareoverflow/blob/main/flowise_s3_loader_object_key_path_traversal_vulndb.md and the VulDB entry at https://vuldb.com/vuln/372611 for any upstream fix releases.