VulnerabilityPublished 8 May 2026Updated 13 May 2026

CVE-2026-41495: czlonkowski n8n-mcp · Sensitive Data in Logs

Affects czlonkowski n8n-mcpSource CVE Database V5

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Not known to be exploited · CVSS 5.3 Medium : upgrade to 2.47.11 when convenient.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

5.3Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 17% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 2.47.11

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: Low
Integrity: None
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: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: None: There is no loss of integrity within 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 8 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 30 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.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), 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 and czlonkowski/n8n-mcp to 2.47.11.

Affected software

Product	Affected	Fixed in
czlonkowskin8n-mcp	Affected <2.47.11	Fixed in 2.47.11
GitHubczlonkowski/n8n-mcp`pkg:github/czlonkowski/n8n-mcp`Other threats	Affected <2.47.11	Fixed in 2.47.11

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 2.47.11 or later, where this logging behavior has been corrected. Until upgraded, restrict access to server logs to trusted personnel only and avoid forwarding logs containing sensitive request metadata to external systems. Patch status is not explicitly stated as 'official-fix' in the vendor advisory, but the description confirms the issue is fixed in version 2.47.11.

Description

### Impact When `n8n-mcp` runs in HTTP transport mode, incoming requests to the `POST /mcp` endpoint had their request metadata written to server logs regardless of the authentication outcome. In deployments where logs are collected, forwarded to external systems, or viewable outside the request trust boundary (shared log storage, SIEM pipelines, support/ops access), this can result in disclosure of: - bearer tokens from the `Authorization` header - per-tenant API keys from the `x-n8n-key` header in multi-tenant setups - JSON-RPC request payloads sent to the MCP endpoint Access control itself was not bypassed — unauthenticated requests were correctly rejected with `401 Unauthorized` — but sensitive values from those rejected requests could still be persisted in logs. Impact category: **CWE-532** (Insertion of Sensitive Information into Log File). ### Affected Deployments running n8n-mcp **v2.47.10 or earlier** in HTTP transport mode (`MCP_MODE=http`). The stdio transport is not affected. ### Patched **v2.47.11** and later. - npm: `npx n8n-mcp@latest` (or pin to `>= 2.47.11`) - Docker: `docker pull ghcr.io/czlonkowski/n8n-mcp:latest` ### Workarounds If users cannot upgrade immediately: - Restrict network access to the HTTP port (firewall, reverse proxy, or VPN) so only trusted clients can reach the endpoint. - Switch to stdio transport (`MCP_MODE=stdio`, the default for CLI invocation), which has no HTTP surface. ### Credit n8n-MCP thanks [@S4nso](https://github.com/S4nso) (Organization / Jormungandr) for reporting this issue.

Impact

Sensitive authentication tokens and request payloads may be exposed through server logs if those logs are accessible to unauthorized parties. This could lead to information disclosure risks, especially in environments where logs are aggregated, forwarded externally, or accessible by support or operations personnel. There is no impact on system integrity or availability, and no bypass of access controls occurs.

Summary

The vulnerability involves insertion of sensitive information into server logs by n8n-mcp versions before 2.47.11 when operating in HTTP transport mode. Incoming POST /mcp requests have their metadata logged regardless of authentication outcome, causing bearer tokens from the Authorization header, tenant API keys from the x-n8n-key header, and JSON-RPC payloads to be written to logs. This can lead to unintended disclosure if logs are collected, forwarded, or accessible beyond the intended trust boundary. The vulnerability does not allow bypassing access controls, as unauthorized requests still receive 401 Unauthorized responses. The issue is fixed in version 2.47.11.

CWE-532Insertion of Sensitive Information into Log File (opens in a new tab)
Base weaknessLikelihood of exploit: MediumOWASP Top 10 A09:2025: Security Logging & Alerting Failures (opens in a new tab)
The product writes sensitive information to a log file.
Architecture and Design · Implementation
Consider seriously the sensitivity of the information written into log files. Do not write secrets into the log files.
Distribution
Remove debug log files before deploying the application into production.
Operation
Protect log files against unauthorized read/write.
OWASP Cheat Sheets
Application Logging Vocabulary (opens in a new tab)
Logging (opens in a new tab)
OWASP ASVS 4.0.3
V7.1.1 (opens in a new tab)
V7.1.2 (opens in a new tab)
V8.3.5 (opens in a new tab)
Attack patterns
Fuzzing for application mapping (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 16 May 2026, 09:41 UTC

WeaknessesCWE-532

Technical details

References

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