n8n-io n8n up to 2.25.6/2.26.1 Task Executor incomplete blacklist

CVSS Meta Temp Score
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CTI Interest Score
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4.5$0-$5k2.00-

Summaryinfo

A vulnerability was found in n8n-io n8n up to 2.25.6/2.26.1. It has been rated as critical. This vulnerability affects unknown code of the component Task Executor Module. The manipulation leads to incomplete blacklist. This vulnerability is traded as CVE-2026-56777. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in n8n-io n8n up to 2.25.6/2.26.1. It has been rated as critical. This issue affects an unknown function of the component Task Executor Module. The manipulation with an unknown input leads to a incomplete blacklist vulnerability. Using CWE to declare the problem leads to CWE-184. The product implements a protection mechanism that relies on a list of inputs (or properties of inputs) that are not allowed by policy or otherwise require other action to neutralize before additional processing takes place, but the list is incomplete, leading to resultant weaknesses. Impacted is confidentiality. The summary by CVE is:

n8n before 2.25.7 and 2.26.x before 2.26.2 contains an abstract syntax tree (AST) security validator bypass in the Python Code node. An authenticated user with permission to create or modify workflows containing a Python Code node can bypass the validator and access the task executor module namespace. The issue only affects self-hosted instances where the Python Task Runner is enabled; where N8N_BLOCK_RUNNER_ENV_ACCESS is configured to allow it, this can disclose environment variables accessible to the task runner process.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-56777 since 06/23/2026. The exploitation is known to be easy. The attack may be initiated remotely. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1562.006 for this issue.

Upgrading to version 2.25.7 or 2.26.2 eliminates this vulnerability.

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Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.6
VulDB Meta Temp Score: 4.5

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.0
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Incomplete blacklist
CWE: CWE-184 / CWE-183 / CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: n8n 2.25.7/2.26.2

Timelineinfo

06/23/2026 CVE reserved
07/01/2026 +8 days Advisory disclosed
07/01/2026 +0 days VulDB entry created
07/01/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-jwm3-qcfw-c5pp
Status: Confirmed

CVE: CVE-2026-56777 (🔒)
GCVE (CVE): GCVE-0-2026-56777
GCVE (VulDB): GCVE-100-375389

Entryinfo

Created: 07/01/2026 09:28
Changes: 07/01/2026 09:28 (77)
Complete: 🔍
Cache ID: 216::103

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