CVE-2026-42231 json
n8n: Prototype Pollution in XML Webhook Body Parser Leads to RCE
published 2026-04-29 6 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-27102 , GHSA-q5f4-99jv-pgg5
- cvss
- 8.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 58%
- public exploits
- 0
- none known
Summary
n8n is an open source workflow automation platform. Prior to versions 1.123.32, 2.17.4, and 2.18.1, a flaw in the xml2js library used to parse XML request bodies in n8n's webhook handler allowed prototype pollution via a crafted XML payload. An authenticated user with permission to create or modify workflows could exploit this to pollute the JavaScript object prototype and, by chaining the pollution with the Git node's SSH operations, achieve remote code execution on the n8n host. This issue has been patched in versions 1.123.32, 2.17.4, and 2.18.1.
Patch / fix
- npm n8n 1.123.32, 2.17.4, 2.18.1
- n8n n8n 1.123.32, 2.17.4, 2.18.1
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 6 mo ago
Exploit prediction
0.85% chance of exploitation in the next 30 days, higher than 58% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 9.4 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H |
| GitHub | 3.1 | 10.0 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
| CNA | 4.0 | 9.4 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | n8n | <1.123.32 >=2.18.0, <2.18.1 >=2.17.0, <2.17.4 |
1.123.32 2.18.1 2.17.4 |
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-q5f4-99jv-pgg5
web, vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-42231
advisory
-
github.com
/n8n-io/n8n
package
Sources
- CVE List CVE-2026-42231
- GitHub Advisory GHSA-q5f4-99jv-pgg5
- NVD CVE-2026-42231
Fencer Vulns 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.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.