Affects widely used AWS EKS networking component; bypasses network isolation enabling lateral movement across many cloud deployments.
CVE-2026-86831
EKS Network Policy Agent ID-collision allows NetworkPolicy bypass
Is CVE-2026-86831 being exploited?
Not confirmed. CVE-2026-86831 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked.
How severe is CVE-2026-86831?
CVE-2026-86831 is rated High with a CVSS score of 8.7. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-86831?
Yes. A fix has been recorded for CVE-2026-86831. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-86831 affect?
CVE-2026-86831 affects aws-network-policy-agent < 1.4.0, amazon-vpc-cni-k8s (Managed Add-on) < 1.22.4, Amazon EKS clusters using AWS VPC CNI and Network Policy Agent. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-86831?
Upgrade aws-network-policy-agent to >=1.4.0 or amazon-vpc-cni-k8s to >=1.22.4
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Authenticated attacker can craft pod/namespace names to cause ID collisions, bypass NetworkPolicy and access co-located pods cross-namespace.
Immediate action required
- affected>= 1.14.0 and < 1.22.4
- affected< 1.4.0
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.