SB2026090292 - Multiple vulnerabilities in n8n

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Main Vulnerability Database SB2026090292

SB2026090292 - Multiple vulnerabilities in n8n

Published: September 2, 2026

Security Bulletin ID SB2026090292
CSH Severity
High
Patch available
YES
Number of vulnerabilities 18
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 6% Medium 28% Low 67%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 18 vulnerabilities.


1) Input validation error (CVE-ID: N/A)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to disclose sensitive information from local Git repositories.

The vulnerability exists due to improper input validation in the Git node branch remote configuration handling when processing fetch or pull operations after setUpstream updates repository configuration. A remote user can set a crafted branch.<name>.remote value to point to a local repository and disclose sensitive information from local Git repositories.

Exploitation requires workflow-edit permission and access to the Git node.


2) Input validation error (CVE-ID: N/A)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to improper input validation in OAuth Dynamic Client Registration endpoints when handling client registration requests. A remote attacker can submit excessively large values in the client_name or grant_types fields to cause a denial of service.

The issue results in persistent growth of stored data because the oversized values are written to the database.


3) Code Injection (CVE-ID: N/A)

CWE-ID: CWE-94 - Improper Control of Generation of Code ('Code Injection')

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to execute arbitrary code.

The vulnerability exists due to improper control of dynamically managed code resources in the expression compiler sanitizer when processing expressions with a class field named __sanitize. A remote user can craft an expression that rebinds the sanitizer and reaches the Function constructor to execute arbitrary code.

On the backend, exploitation runs code in the n8n process. In the editor preview, a member\'s expression can run as JavaScript in the session of whoever opens the workflow.


4) Improper access control (CVE-ID: N/A)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to bypass an approval gate and resume a paused execution.

The vulnerability exists due to improper access control in the /chat WebSocket route when resuming a paused execution from a reused resume token. A remote attacker can present a resume token obtained as an anonymous form submitter to bypass an approval gate and resume a paused execution.

Exploitation requires a resume token that was handed to an anonymous form submitter.


5) Improper access control (CVE-ID: N/A)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to disclose workflow IDs, version IDs, activation-error details, and lifecycle event information across users.

The vulnerability exists due to improper access control in the /rest/active-workflows endpoint and workflow lifecycle event push mechanism when handling requests and broadcasting workflow events without applying a userId-based sharing filter. A remote user can access the active workflow listing or receive broadcast events to disclose workflow IDs, version IDs, activation-error details, and lifecycle event information across users.

The active workflow listing was exposed to any member regardless of sharing, and workflow activation, deactivation, and publication events were broadcast to every connected client.


6) Improper access control (CVE-ID: N/A)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to disclose sensitive information.

The vulnerability exists due to improper access control in log streaming event destination credential resolution when resolving a referenced generic HTTP credential. A remote privileged user can name a credential belonging to another project and send its decrypted secret to an attacker-controlled endpoint to disclose sensitive information.

Exploitation requires a custom global role scoped to log streaming operations.


7) Improper access control (CVE-ID: N/A)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to disclose sensitive information.

The vulnerability exists due to improper access control in the role assignment endpoints `/rest/roles/:slug/assignments` and `/rest/roles/:slug/assignments/:projectId/members` when handling requests for project role assignments. A remote privileged user can specify an arbitrary project on the instance and read back its members\' names and email addresses to disclose sensitive information.

The issue enables cross-tenant disclosure of project-member personally identifiable information.


8) Prototype pollution (CVE-ID: N/A)

CWE-ID: CWE-1321 - Improperly Controlled Modification of Object Prototype Attributes (\'Prototype Pollution\')

CVSSv4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to cause a denial of service.

The vulnerability exists due to improper control of dynamically managed code resources in workflow structure summary generation when processing a stored workflow submitted through the REST API. A remote user can submit a crafted workflow containing reserved keys such as __proto__ to cause a denial of service.

Only the Instance AI workflow summary code path is affected.


9) Origin validation error (CVE-ID: N/A)

CWE-ID: CWE-346 - Origin Validation Error

CVSSv4: 7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to improper origin validation in Instance AI credential setup when processing fetched content during the credential setup flow. A remote attacker can inject an attacker-controlled URL into the setup flow to disclose sensitive information.

User interaction is required to actively inject the attacker-controlled URL into the setup flow.


10) Improper access control (CVE-ID: N/A)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to disclose sensitive information.

The vulnerability exists due to improper access control in the Git node when processing a relative remote URL during fetch or pull operations. A remote user can configure a nested repository and use the same relative remote URL to cause git to resolve it outside the intended file sandbox and disclose sensitive information.

The issue occurs because the URL was validated against the configured repository path, but git resolved it from the enclosing repository\'s top-level working directory.


11) Path traversal (CVE-ID: N/A)

CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CVSSv4: 0 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to access unintended Elasticsearch endpoints.

The vulnerability exists due to improper input validation in Elasticsearch and ElasticSecurity nodes when building REST request paths from user-provided identifiers. A remote user can supply a specially crafted identifier containing path separators or dot segments to access unintended Elasticsearch endpoints.

Requests are sent under the stored Elasticsearch credential.


12) Missing Authentication for Critical Function (CVE-ID: N/A)

CWE-ID: CWE-306 - Missing Authentication for Critical Function

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to send spoofed webhook deliveries.

The vulnerability exists due to improper authentication in GitHub Trigger webhook signature verification when reusing an existing webhook after a 422 create response. A remote attacker can send crafted requests to the workflow webhook URL to send spoofed webhook deliveries.

The issue occurs when a webhook for the URL already exists and the generated signing secret is not stored, causing signature verification to fail open.


13) Inefficient regular expression complexity (CVE-ID: N/A)

CWE-ID: CWE-1333 - Inefficient Regular Expression Complexity

CVSSv4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to cause a denial of service.

The vulnerability exists due to inefficient regular expression complexity in the default blocked-file-pattern match in the Git node clone operation when processing a crafted destination path. A remote user can supply a specially crafted clone path to cause a denial of service.

Evaluation occurs synchronously in the main process, and a single workflow execution can freeze the instance for other users.


14) Improper access control (CVE-ID: N/A)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to disclose sensitive information.

The vulnerability exists due to improper access control in the Agent workflow tool path when invoking a workflow attached to an Agent as a tool. A remote user can attach or use a restricted workflow through an Agent to disclose sensitive information.

The workflow\'s \"This workflow can be called by\" setting is enforced for the Execute Workflow node but was not consulted on the Agent tool path.


15) Improper access control (CVE-ID: N/A)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to disclose sensitive information.

The vulnerability exists due to improper access control in the model-search endpoint of the OpenAI Chat Model node when processing requests with a user-supplied options.baseURL. A remote user can send a specially crafted request to disclose sensitive information.

The issue affects the model-search dropdown path, which could reach an arbitrary host with the credential attached despite an administrator-configured allowed-domains restriction.


16) Improper access control (CVE-ID: N/A)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to obtain a valid session.

The vulnerability exists due to improper access control in the public OIDC login and callback endpoints when handling OIDC authentication requests. A remote user can send requests to the endpoints to obtain a valid session.

The issue affects enterprise instances where OIDC was configured at least once and later disabled.


17) Improper Authorization (CVE-ID: N/A)

CWE-ID: CWE-285 - Improper Authorization

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to delete workflows and credentials across projects.

The vulnerability exists due to improper authorization in the source control push endpoint when processing a push request with file paths and status from the request payload. A remote privileged user can submit a crafted push request naming files from other projects to delete workflows and credentials across projects.

The issue is exploitable only when the Source Control (Environments) enterprise feature is licensed, enabled, and connected to a remote repository.


18) Code Injection (CVE-ID: N/A)

CWE-ID: CWE-94 - Improper Control of Generation of Code ('Code Injection')

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to execute arbitrary code.

The vulnerability exists due to improper control of code generation in the legacy expression engine when processing expressions that tamper with the global JSON.stringify value and inject code into generated source. A remote user can supply a crafted expression to execute arbitrary code.

Only instances running the legacy expression engine are vulnerable. The default vm expression engine is not affected.


Remediation

Install update from vendor's website.

References