CVE-2026-42449VulnerabilityPublished 30 Apr 2026Updated 11 May 2026

n8n-mcp's IPv4-mapped IPv6 addresses bypass SSRF protection in validateUrlSync(), enabling full SSRF for SDK embedders

Affects n8n-mcpSource GCVE Database

Authoritative record:CVE-2026-42449· High 8.5

Not known to be exploited · CVSS 8.5 High : upgrade to 2.47.14 soon.

Data as of 27 Oct 2026, 01:11 UTC

CVSS 3.1 base score

8.5High

How severe the flaw is on the 0–10 CVSS scale.

Patch: Available – fixed in 2.47.14

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Changed
Confidentiality: High
Integrity: Low
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Changed: An exploited vulnerability can affect resources beyond the security scope managed by the security authority of the vulnerable component. In this case, the vulnerable component and the impacted component are different and managed by different security authorities.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 7 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade n8n-mcp to 2.47.14.

Affected software

Product	Affected	Fixed in
npmn8n-mcp	Affected >=2.47.4 <2.47.14	Fixed in 2.47.14

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Upgrade n8n-mcp to version 2.47.14 or later, where the vulnerability is fixed. If immediate upgrade is not possible, validate URLs before passing them to the SDK by rejecting any n8nApiUrl with IP literal hostnames (IPv6 or IPv4) and accept only DNS-resolvable hostnames. Additionally, restrict outbound network traffic from the n8n-mcp process to block RFC1918 private IP ranges, link-local addresses (169.254.0.0/16), and cloud metadata endpoints as a defense-in-depth measure. Avoid accepting user-controlled n8nApiUrl values if possible by deriving URLs from internal configuration only.

Description

A Server-Side Request Forgery (SSRF) vulnerability exists in n8n-mcp versions 2.47.4 through 2.47.13 in the synchronous URL validator validateUrlSync(). It fails to check IPv4-mapped IPv6 addresses, allowing attackers supplying a crafted n8nApiUrl to bypass protections and make HTTP requests to cloud metadata services, private networks, or localhost. The vulnerability allows response data to be returned to the attacker and forwards the n8nApiKey header to the target. The issue is fixed in version 2.47.14.

Impact

An attacker able to supply a malicious n8nApiUrl can cause the server to perform SSRF attacks to internal cloud metadata services, private IP ranges, and localhost services, potentially exposing sensitive data. The vulnerability allows the attacker to receive response data from these internal endpoints and causes the server to forward the n8nApiKey in requests, increasing the risk of credential exposure. This can lead to unauthorized access to cloud instance metadata and internal network resources.

CWE-918Server-Side Request Forgery (SSRF) (opens in a new tab)
Base weaknessCWE Top 25 (2025): #22OWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.
OWASP Cheat Sheets
Server Side Request Forgery Prevention (opens in a new tab)
Unvalidated Redirects and Forwards (opens in a new tab)
Cross Site Scripting Prevention (opens in a new tab)
DOM based XSS Prevention (opens in a new tab)
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V12.6.1 (opens in a new tab)
V5.2.6 (opens in a new tab)
Attack patterns
Server Side Request Forgery (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 27 Oct 2026, 01:11 UTC

WeaknessesCWE-918

Technical details

References

Community reviews

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