CVE-2026-42449VulnerabilityPublished 13 Aug 2026Updated 26 Oct 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 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score

8.5High

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
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
Homebrewn8n-mcp`pkg:brew/n8n-mcp`Other threats	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

A patch is available in n8n-mcp version 2.47.14 and later; upgrading to this version is strongly recommended. For those unable to upgrade immediately, the following workarounds are advised: 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; 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; avoid accepting user-controlled n8nApiUrl values by deriving URLs from internal configuration only. These mitigations provide defense-in-depth and reduce the risk of exploitation.

Description

A Server-Side Request Forgery (SSRF) vulnerability exists in the n8n-mcp SDK embedder path versions 2.47.4 through 2.47.13. The synchronous URL validator in SSRFProtection.validateUrlSync() fails to check IPv4-mapped IPv6 addresses, allowing bypass of protections against cloud metadata, localhost, and private IP ranges. An attacker controlling the n8nApiUrl parameter can cause the server to make HTTP requests to internal or cloud metadata endpoints and receive response data, with the n8nApiKey header forwarded to the attacker-controlled target. This vulnerability is fixed in version 2.47.14.

Impact

An attacker with the ability to supply the n8nApiUrl parameter to the vulnerable SDK embedder can cause the server to issue HTTP requests to internal resources such as cloud metadata endpoints and private networks. This can lead to unauthorized data disclosure (confidentiality impact) as response bodies are returned to the attacker. Additionally, the n8nApiKey is forwarded to the attacker-controlled target, potentially exposing sensitive credentials. The vulnerability does not affect the primary HTTP server deployment due to additional validation. The CVSS v3.1 score is 8.5 (high severity) reflecting network attack vector, low complexity, low privileges required, no user interaction, scope change, high confidentiality impact, low integrity impact, and no availability impact.

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 17:14 UTC

Technical details

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