CVE-2026-59206 json
n8n: Prototype Pollution via Workflow Credentials Leads to Unauthenticated User and Project Enumeration
published 4mo ago modified 17d ago also GHSA-75qm-gp28-rcq9 , EUVD-2026-42612
- cvss
- 7.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 52%
- public exploits
- 0
- none known
Summary
n8n is an open source workflow automation platform. Prior to 1.123.61, 2.27.4, and, 2.28.1, an authenticated user with the default workflow:create permission could pollute Object.prototype through a crafted workflow saved, updated, or imported via the workflow API, allowing unauthenticated requests to be treated as a privileged user and exposing user and project listing endpoints. This issue is fixed in versions 1.123.61, 2.27.4, and 2.28.1.
Patch / fix
- npm n8n 1.123.61, 2.27.4, 2.28.1
- n8n n8n 1.123.61, 2.27.4
Is CVE-2026-59206 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4mo ago
Exploit prediction
0.66% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:L/SI:L/SA:N |
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:L/SI:L/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 |
| NVD | 3.1 | 7.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:L |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | n8n | <1.123.61 >=2.28.0, <2.28.1 >=2.0.0-rc.0, <2.27.4 |
1.123.61 2.28.1 2.27.4 |
Affected products
- n8n-io n8n
Classification
- Weakness
-
- CWE-1321 Improperly Controlled Modification of Object Prototype Attributes
References
-
github.com
/n8n-io/n8n/security/advisories/GHSA-75qm-gp28-rcq9
web, vendor-advisory
-
github.com
/n8n-io/n8n/releases/tag/n8n%402.27.4
web, release-notes
-
github.com
/n8n-io/n8n/releases/tag/n8n%402.28.1
web, release-notes
-
nvd.nist.gov
/vuln/detail/CVE-2026-59206
advisory
-
github.com
/n8n-io/n8n
package
Sources
- CVE List CVE-2026-59206
- GitHub Advisory GHSA-75qm-gp28-rcq9
- NVD CVE-2026-59206
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.