Security readout for executives and security teams
Plain-English summary
In specific multi-tenant HTTP deployments, n8n-MCP could let one authenticated tenant access or destroy another tenant's workflow version backups. Those backups may include workflow details, credential references, and authorization headers. This is a critical tenant-isolation failure, fixed in n8n-mcp 2.56.1.
Executive priority
Treat as urgent for any hosted or shared n8n-MCP environment. The risk is cross-customer data exposure and destructive backup loss from an authenticated tenant, not just administrator misuse.
Technical view
Before 2.56.1, n8n-mcp did not isolate local workflow version history backups per tenant when HTTP mode used ENABLE_MULTI_TENANT=true. The issue maps to broken authorization and cross-tenant object access, allowing low-privileged authenticated network users to read, delete, or destroy backups outside their tenant boundary.
Likely exposure
Exposure is limited to czlonkowski n8n-mcp versions before 2.56.1 running in HTTP mode with multi-tenancy enabled through ENABLE_MULTI_TENANT=true.
Exploitation context
The provided sources do not report active exploitation, and the CVE is not marked KEV. Exploitation requires an authenticated tenant account but no user interaction, with network access and low attack complexity.
Researcher notes
Focus validation on tenant-boundary enforcement around workflow version backup storage and deletion paths. Do not assume all n8n or MCP deployments are affected; the source scope is n8n-mcp before 2.56.1 with HTTP multi-tenancy enabled.
Mitigation direction
- Upgrade n8n-mcp to version 2.56.1 or later.
- Check the GitHub advisory and release notes for vendor guidance.
- Restrict access to affected HTTP deployments until upgraded.
- Preserve workflow backup evidence before cleanup or migration.
- Review tenant account activity for unusual backup reads or deletions.
Validation and detection
- Inventory n8n-mcp deployments and record running versions.
- Confirm whether HTTP mode is used with ENABLE_MULTI_TENANT=true.
- Check whether local workflow version history backups exist.
- Verify upgraded instances report n8n-mcp 2.56.1 or later.
- Review logs for cross-tenant backup access or deletion indicators.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-639: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCWE-862: Authorization and privilege behavior lookup
Authorization weaknesses can support privilege escalation and valid-account review, depending on exploit path. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-54052 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L3.16GitHub_MVulnerability scoring details
Base CVSS 3.1 score
9.9CriticalVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/czlonkowski/n8n-mcp/security/advisories/GHSA-j6r7-6fhx-77wxCVE reference, GitHub_M · x_refsource_CONFIRM
- https://github.com/czlonkowski/n8n-mcp/releases/tag/v2.56.1CVE reference, GitHub_M · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Authorization Bypass Through User-Controlled Key
Authorization Bypass Through User-Controlled Key represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Missing Authorization
Missing Authorization represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.