FlowiseAI Flowise up to 3.1.2 S3 Document Loader S3.ts path traversal

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.7$0-$5k3.45

Summaryinfo

A vulnerability, which was classified as critical, has been found in FlowiseAI Flowise up to 3.1.2. This affects an unknown function of the file packages/components/nodes/documentloaders/S3/S3.ts of the component S3 Document Loader. The manipulation leads to path traversal. This vulnerability is documented as CVE-2026-12821. The attack can be initiated remotely. Additionally, an exploit exists. The vendor was contacted early about this disclosure but did not respond in any way.

Detailsinfo

A vulnerability, which was classified as critical, has been found in FlowiseAI Flowise up to 3.1.2. This issue affects an unknown functionality of the file packages/components/nodes/documentloaders/S3/S3.ts of the component S3 Document Loader. The manipulation with an unknown input leads to a path traversal vulnerability. Using CWE to declare the problem leads to CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. Impacted is confidentiality, integrity, and availability.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-12821. The exploitation is known to be easy. The attack may be initiated remotely. Technical details as well as a exploit are known. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 06/22/2026). The attack technique deployed by this issue is T1006 according to MITRE ATT&CK.

It is declared as proof-of-concept. The vendor was contacted early about this disclosure but did not respond in any way.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at EUVD (EUVD-2026-38202) and CERT Bund (WID-SEC-2026-2023). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Open Source Flowise

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 5.7

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Path traversal
CWE: CWE-22
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Proof-of-Concept
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

06/21/2026 Advisory disclosed
06/21/2026 +0 days VulDB entry created
06/22/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Not defined

CVE: CVE-2026-12821 (🔒)
GCVE (CVE): GCVE-0-2026-12821
GCVE (VulDB): GCVE-100-372611
EUVD: 🔒
CERT Bund: WID-SEC-2026-2023 - Flowise: Schwachstelle ermöglicht Manipulation von Dateien

scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 06/21/2026 15:15
Updated: 06/22/2026 13:11
Changes: 06/21/2026 15:15 (54), 06/22/2026 03:18 (1), 06/22/2026 13:11 (7)
Complete: 🔍
Submitter: ST4R
Cache ID: 216::103

Submitinfo

Accepted

  • Submit #837578: FlowiseAI/Flowise - `packages/components/nodes/documentloaders/S3/S3.ts` - `S3Directory / S3File document loader temporary-file handling` 3.1.2 Path Traversal / Arbitrary Local File Write / Unsafe Cleanup (by ST4R)

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion

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