Vulnerability Description
Portainer Community Edition is a lightweight service delivery platform for containerized applications that can be used to manage Docker, Swarm, Kubernetes and ACI environments. From 2.33.0 to before 2.33., Portainer proxies requests to Kubernetes clusters through a middleware layer (kubeClientMiddleware) that validates the requesting user's token before forwarding traffic to the cluster. When security.RetrieveTokenData returned an error, the middleware wrote an HTTP 403 response but was missing a return statement — execution continued into the handler with a nil tokenData value. The Kubernetes endpoints sit behind Portainer's outer AuthenticatedAccess bouncer, so an attacker requires a valid Portainer session. However, a user whose secondary token validation fails in kubeClientMiddleware — for example a user without permission to access a given Kubernetes endpoint — would have their request forwarded to the cluster anyway, bypassing the authorization check. The same defect was present in both the CE and EE codebases. This vulnerability is fixed in 2.33.8.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Portainer | Portainer | >= 2.33.0, < 2.33.8 |
Related Weaknesses (CWE)
References
- https://github.com/portainer/portainer/security/advisories/GHSA-mgq6-4x29-88r3ExploitThird Party Advisory
FAQ
What is CVE-2026-44882?
CVE-2026-44882 is a vulnerability with a CVSS score of 8.1 (HIGH). Portainer Community Edition is a lightweight service delivery platform for containerized applications that can be used to manage Docker, Swarm, Kubernetes and ACI environments. From 2.33.0 to before 2...
How severe is CVE-2026-44882?
CVE-2026-44882 has been rated HIGH with a CVSS base score of 8.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-44882?
Check the references section above for vendor advisories and patch information. Affected products include: Portainer Portainer.