CVE-2026-59208
HIGH 7.6n8n is an open source workflow automation platform. Prior to 2.27.4 and from 2.28.0 prior to 2.28.1, n8n instances configured with more than one trusted token-exchange issuer resolved external identities to local accounts using only the JWT sub claim and ignored the iss claim, allowing an attacker with a valid token from one trusted issuer and a sub matching a victim under another issuer to authenticate as that victim. This issue is fixed in versions 2.27.4 and 2.28.1.
Severe if exploited (CVSS 7.6), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.1%chance of exploitation in 30 days · 4th percentile
Impact if exploited
7.6CVSS 4.0 · HIGH
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityNone
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ⚠Privileges: Requires a low-privilege account
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
- ⚠Requirements: Specific conditions must be present
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-59208/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-59208/poc.json
Weakness (CWE)
- CWE-287: : Improper Authentication
- CWE-346: : Origin Validation Error
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
Known Affected Software Configurations
| Vendor | Product | Version range |
|---|---|---|
| N8n | N8n | < 2.27.4 |
| N8n | N8n | 2.28.0 |
All CVSS metrics
- HIGH 7.6 v4.0 · CNA Primary
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N - HIGH 7.6 v4.0 · NVD Secondary
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/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 - MEDIUM 6.8 v3.1 · NVD Primary
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N