n8n-io n8n up to 1.123.88/2.45.4/2.46.0/3.0.0 MCP OAuth Dynamic Client Registration redirect_uri

Summaryinfo

A vulnerability marked as problematic has been reported in n8n-io n8n up to 1.123.88/2.45.4/2.46.0/3.0.0. Affected by this issue is some unknown functionality of the component MCP OAuth Dynamic Client Registration. The manipulation of the argument redirect_uri leads to redirect. This vulnerability is documented as CVE-2026-126386. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in n8n-io n8n up to 1.123.88/2.45.4/2.46.0/3.0.0 and classified as problematic. This issue affects an unknown code of the component MCP OAuth Dynamic Client Registration. The manipulation of the argument redirect_uri with an unknown input leads to a redirect vulnerability. Using CWE to declare the problem leads to CWE-601. The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect. Impacted is integrity. The summary by CVE is:

n8n before 1.123.89, 2.x before 2.45.5, 2.46.x before 2.46.1, and 3.x before 3.0.1 contains an open redirect vulnerability in the unauthenticated MCP OAuth dynamic client registration flow, which accepts arbitrary redirect_uri values via the /mcp-oauth/register endpoint. Attackers can send victims crafted /mcp-oauth/authorize URLs that redirect them to attacker-controlled sites before instance checks run, enabling phishing.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-126386 since 11/10/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1204.001 according to MITRE ATT&CK.

Upgrading to version 1.123.89, 2.45.5, 2.46.1 or 3.0.1 eliminates this vulnerability.

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

Productinfo

Vendor

• n8n-io

Name

• n8n

Version

• 1.123.0
• 1.123.1
• 1.123.2
• 1.123.3
• 1.123.4
• 1.123.5
• 1.123.6
• 1.123.7
• 1.123.8
• 1.123.9
• 1.123.10
• 1.123.11
• 1.123.12
• 1.123.13
• 1.123.14
• 1.123.15
• 1.123.16
• 1.123.17
• 1.123.18
• 1.123.19
• 1.123.20
• 1.123.21
• 1.123.22
• 1.123.23
• 1.123.24
• 1.123.25
• 1.123.26
• 1.123.27
• 1.123.28
• 1.123.29
• 1.123.30
• 1.123.31
• 1.123.32
• 1.123.33
• 1.123.34
• 1.123.35
• 1.123.36
• 1.123.37
• 1.123.38
• 1.123.39
• 1.123.40
• 1.123.41
• 1.123.42
• 1.123.43
• 1.123.44
• 1.123.45
• 1.123.46
• 1.123.47
• 1.123.48
• 1.123.49
• 1.123.50
• 1.123.51
• 1.123.52
• 1.123.53
• 1.123.54
• 1.123.55
• 1.123.56
• 1.123.57
• 1.123.58
• 1.123.59
• 1.123.60
• 1.123.61
• 1.123.62
• 1.123.63
• 1.123.64
• 1.123.65
• 1.123.66
• 1.123.67
• 1.123.68
• 1.123.69
• 1.123.70
• 1.123.71
• 1.123.72
• 1.123.73
• 1.123.74
• 1.123.75
• 1.123.76
• 1.123.77
• 1.123.78
• 1.123.79
• 1.123.80
• 1.123.81
• 1.123.82
• 1.123.83
• 1.123.84
• 1.123.85
• 1.123.86
• 1.123.87
• 1.123.88
• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6
• 2.7
• 2.8
• 2.9
• 2.10
• 2.11
• 2.12
• 2.13
• 2.14
• 2.15
• 2.16
• 2.17
• 2.18
• 2.19
• 2.20
• 2.21
• 2.22
• 2.23
• 2.24
• 2.25
• 2.26
• 2.27
• 2.28
• 2.29
• 2.30
• 2.31
• 2.32
• 2.33
• 2.34
• 2.35
• 2.36
• 2.37
• 2.38
• 2.39
• 2.40
• 2.41
• 2.42
• 2.43
• 2.44
• 2.45
• 2.45.0
• 2.45.1
• 2.45.2
• 2.45.3
• 2.45.4
• 2.46.0
• 3.0

Website

• Product: https://github.com/n8n-io/n8n/

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