CVE-2026-118678high7.1

n8n before 2.41.4 and 2.42.1 Prototype Pollution DoS via Workflow History Compaction

Impact

n8n versions before 2.41.4 and 2.42.x before 2.42.1 have a prototype pollution vulnerability, allowing low-privileged users to alter built-in object behavior. Attackers can cause server errors by adding specially named connection keys. This affects logins and writes.

Summarized by @cf/meta/llama-3.3-70b-instruct-fp8-fast. Verify details against the original sources.

Affected packages

This source has no supported package-version data for matching. You can read the advisory here, but this record alone cannot power a dependency check.

Affected products

Vendor version evidence. Product records are separate from automatic dependency matching.

n8n-io · VulnCheck

n8n

2 ranges

VulnCheck version evidence

Package identity

pkg:npm/n8nExplore n8n →

Identity supplied by VulnCheck. Version matching requires compatible range evidence.

Check a product version

Compare with this publisher’s ranges. This does not inspect your installation.

affected

0 → before 2.41.4

semver versions

unaffected

2.41.4

semver versions

Other versions: unaffected

n8n-io · VulnCheck

n8n

2 ranges

VulnCheck version evidence

Package identity

pkg:npm/n8nExplore n8n →

Identity supplied by VulnCheck. Version matching requires compatible range evidence.

Check a product version

Compare with this publisher’s ranges. This does not inspect your installation.

affected

2.42.0 → before 2.42.1

semver versions

unaffected

2.42.1

semver versions

Other versions: unaffected

Original source description

n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability that allows low-privileged users to alter built-in object behaviour by saving workflows with specially named connection keys. Attackers can add keys such as proto to workflow connections, which the periodic history compaction task processes, causing logins and writes to fail with server errors.

Inside the record

Evidence available

Package identity

Version evidence

Remediation guidance · not supplied

Weakness classification

Additional publishers

Describes the evidence in this view, not whether the product is safe.

Original records

CVE-2026-118678

View the latest unmodified CVE JSON from the official source. It may be newer than this imported page.

cve.new JSON →

Underlying weaknesses

The source’s classification of what caused the vulnerability.

CWE-1321 ↗

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

VulnCheck

Environment requirements

These conditions apply together as specified by the publisher. A matching product name alone does not establish exposure.

VulnCheck · platform conditions

Any condition may hold

Vulnerable product

cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:*

From (inclusive):

After:

Through (inclusive):

Before: 2.41.4

Any condition may hold

Vulnerable product

cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:*

From (inclusive): 2.42.0

After:

Through (inclusive):

Before: 2.42.1

Original applicability statements

[
  {
    "nodes": [
      {
        "operator": "OR",
        "negate": false,
        "cpeMatch": [
          {
            "vulnerable": true,
            "criteria": "cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "2.41.4"
          }
        ]
      }
    ]
  },
  {
    "nodes": [
      {
        "operator": "OR",
        "negate": false,
        "cpeMatch": [
          {
            "vulnerable": true,
            "criteria": "cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:*",
            "versionStartIncluding": "2.42.0",
            "versionEndExcluding": "2.42.1"
          }
        ]
      }
    ]
  }
]

Contributing organizations · 2

VulnCheck

Assigning organization

2026-10-28

CISA-ADP

Additional data publisher

2026-10-29

What changed

Follow changes

CVE · CVE-2026-1186782026-10-29

Observed 2026-10-29T21:32:44.505Z · upstream updated 2026-10-29T20:54:29.021Z

Prioritization updated

before

[]

after

[
  {
    "source": "CISA-ADP",
    "type": "SSVC",
    "role": "CISA Coordinator",
    "timestamp": "2026-10-29T15:28:50.969331Z",
    "decisions": [
      {
        "name": "Exploitation",
        "value": "none"
      },
      {
        "name": "Automatable",
        "value": "no"
      },
      {
        "name": "Technical Impact",
        "value": "partial"
      }
    ]
  }
]

Large field values are marked as truncated previews. Original source snapshots remain retained.

Showing up to 50 most recent observed changes.

References

2 sources

github.com/n8n-io/n8n/security/advisories/GHSA-fvv4-gmv9-xqf5

vendor-advisoryVulnCheck

www.vulncheck.com/advisories/n8n-before-2.41.4-and-2.42.1-prototype-pollution-dos-via-workflow-history-compaction

third-party-advisoryVulnCheck

Priority and evidence

Not in CISA KEVNo package fix recorded

KEV coverage does not rule out exploitation.

KEV checked 31/10/2026, 05:35:31 UTC

VulnCheck · CVSS:4.0 · 7.1

Assessment vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

VulnCheck · CVSS:3.1 · 7.1

Assessment vector

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

The headline uses the highest imported catalog score. Assessments can differ by source and CVSS version.

Reading the signals

Severity · CVSS: Technical impact and attack conditions. The headline is the highest imported catalog score; sources may disagree.
Observed exploitation · KEV: An absent or unavailable KEV listing does not establish that exploitation has not occurred.
Predicted exploitation · EPSS: 0.29% estimated probability in the next 30 days. 2026-10-29 · FIRST EPSS.

CISA-ADP · SSVC

CISA Coordinator · 2026-10-29

Exploitation: none
Automatable: no
Technical Impact: partial

SSVC describes the publisher’s decision context. Your organization’s exposure and priorities may differ.

Record details

Published: 28/10/2026, 18:59:50 UTC
Modified: 29/10/2026, 20:54:29 UTC
Last imported by cve.new: 29/10/2026, 21:32:44 UTC
Aliases: None recorded

Source evidence

Request a correction or dispute

Start with the assigning organization for this record. Include the CVE ID, the disputed information, and supporting evidence. A dispute does not itself reject a record.

Find the responsible CNA →Official dispute and escalation process ↗

CVE CVE-2026-118678

Enrichment coverage

NVDAvailable

Checked 30/10/2026, 01:55:39 UTC

GHSAAvailable

Checked 30/10/2026, 01:55:38 UTC

EUVDAvailable

Checked 30/10/2026, 01:55:41 UTC

EPSSAvailable

Checked 30/10/2026, 01:55:40 UTC

Additional source evidence

GitHub Advisory Database · GHSA-4v4v-jr32-r382

CVSS 7.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H

Checked 30/10/2026, 01:55:38 UTC

NVD · CVE-2026-118678

CVSS 7.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Checked 30/10/2026, 01:55:39 UTC

NVD · CVE-2026-118678

CVSS 7.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H

Checked 30/10/2026, 01:55:39 UTC

FIRST EPSS · CVE-2026-118678

EPSS 0.29% probability of exploitation in the next 30 days. Percentile: 21.93% · 2026-10-29

Checked 30/10/2026, 01:55:40 UTC

ENISA EUVD · EUVD-2026-112384

CVSS 7.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

Checked 30/10/2026, 01:55:41 UTC

Sponsored by MoxsoBuild security habits with adaptive training and phishing simulations.View as JSON

Investigate in your agent.

n8n before 2.41.4 and 2.42.1 Prototype Pollution DoS via Workflow History Compaction

Impact

Affected packages

Affected products

n8n

affected

unaffected

unknown

n8n

affected

unaffected

unknown

Original source description

Inside the record

Evidence available

Original records

Underlying weaknesses

Environment requirements

What changed

References