CVE-2026-66780
CRITICAL 9.9A flaw was found in the submariner-operator component. The `submariner-k8s-broker-cluster` Role, which is assigned to joined clusters, possesses excessive permissions. This allows a compromised cluster to alter network configurations, specifically by overwriting other clusters' endpoint information. Consequently, an attacker can redirect inter-cluster tunnel traffic, enabling a Man-in-the-Middle (MITM) attack across the entire cluster mesh.
Severe if exploited (CVSS 9.9), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.2%chance of exploitation in 30 days · 15th percentile
Impact if exploited
9.9CVSS 3.1 · CRITICAL
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityHigh
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
✓ 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-2026-66780/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-2026-66780/poc.json
Weakness (CWE)
- CWE-284: Improper Access Control
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
All CVSS metrics
- CRITICAL 9.9 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - CRITICAL 9.9 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H