VulnerabilityPublished 13 Aug 2026Updated 26 Oct 2026

CVE-2026-54052: n8n-MCP · Cross-tenant access to workflow version backups in multi-tenant HTTP deployments

Affects n8n-mcpSource GCVE Database

Authoritative record:CVE-2026-54052· Critical 9.9

Not known to be exploited · CVSS 9.9 Critical : upgrade to 2.56.1 as a priority.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score

9.9Critical

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

EPSS: 0.3% chance of exploitation in 30 days – higher than 32% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 2.56.1

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

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

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: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 15 Jul 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 2.56.1.

Affected software

Product	Affected	Fixed in
Homebrewn8n-mcp`pkg:brew/n8n-mcp`Other threats	Affected >=2.14.1 <2.56.1	Fixed in 2.56.1

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

AI-suggested

Upgrade to n8n-mcp version 2.56.1 or later, which includes a fix isolating workflow version backups per tenant and a migration to clear un-scoped backups. If immediate upgrade is not possible, disable the workflow version tool by setting DISABLED_TOOLS=n8n_workflow_versions in the server environment to block cross-tenant access. Alternatively, avoid multi-tenant mode by deploying separate instances per tenant with isolated databases. Restrict network access to the HTTP endpoint to trusted operators to reduce exposure.

Description

CVE-2026-54052 is a critical vulnerability in n8n-mcp affecting multi-tenant HTTP deployments up to version 2.56.0. It allows authenticated tenants to access and manipulate workflow version backups belonging to other tenants due to lack of isolation. These backups contain sensitive node definitions including credential references, posing confidentiality, integrity, and availability risks. The issue is fixed in version 2.56.1 by isolating stored version history per tenant instance.

Impact

An authenticated tenant in a multi-tenant HTTP deployment can access confidential workflow backup data of other tenants, including credential references and authorization headers, leading to a confidentiality breach. Additionally, the tenant can delete or destroy other tenants' backups, impacting integrity and availability of stored workflow versions. This vulnerability poses a critical risk in shared deployment environments.

Summary

In multi-tenant HTTP deployments of n8n-mcp (versions <= 2.56.0), the workflow version backups are not properly isolated per tenant. This allows an authenticated tenant to read and delete workflow version snapshots of other tenants. Since snapshots include full node definitions with credential references and authorization headers, this vulnerability exposes sensitive data and allows unauthorized modification or deletion of backups. The vulnerability does not affect stdio or single-tenant HTTP deployments. The fix in version 2.56.1 isolates stored version history per tenant and includes a migration that clears un-scoped backups. Workarounds include disabling the workflow version tool or avoiding multi-tenant mode.

References

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Exploitation evidence

What to do

Affected software

Description

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

Technical details

References

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