# CVE-2026-122266: Improper isolation of shared resources in aws-network-policy-agent in Amazon EKS


- **Severity:** Medium 6.3 (`CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 4 Nov 2026
- **Updated:** 9 Nov 2026

## What is CVE-2026-122266?

CVE-2026-122266 is a medium-severity vulnerability in AWS amazon-vpc-cni-k8s, published on 4 Nov 2026. 

### Official description

Improper isolation of shared resources in aws-network-policy-agent in Amazon EKS Network Policy Agent before 1.3.7 (VPC CNI before 1.22.3) might allow an authenticated adjacent user to bypass NetworkPolicy ingress enforcement on co-located pods via eBPF conntrack map poisoning using crafted AF_PACKET frames.

To remediate this issue, users should upgrade to Amazon VPC CNI Managed Add-on v1.22.3 or later (which includes Network Policy Agent v1.3.7).

Weakness: CWE-1189 (Improper Isolation of Shared Resources on System-on-a-Chip (SoC))

## Which versions are affected by CVE-2026-122266?


## How do I fix CVE-2026-122266?

No fix has been published for CVE-2026-122266 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-122266 being exploited?

There is no known exploitation of CVE-2026-122266 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-122266 and fix it if it is affected.

What it is: CVE-2026-122266 is a medium-severity vulnerability in AWS amazon-vpc-cni-k8s, published on 4 Nov 2026. 
Exploitation: There is no known exploitation of CVE-2026-122266 in the wild and no public exploit code.

Affected product: AWS amazon-vpc-cni-k8s. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-122266/ (Markdown: https://insights.sbomify.com/CVE-2026-122266/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-122266
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-122266
- OSV: https://osv.dev/vulnerability/CVE-2026-122266

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-122266/
Summaries are generated and may contain mistakes; the official description above is the record.