CVE-2026-55761

MediumCVSS 5.9

Published: 08/07/2026(UTC)Updated: 10/07/2026(UTC)Translated: 11/07/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.31%

23th percentile - higher than 23% of all known CVEs

Summary

A vulnerability in Portainer Community Edition allows an unauthenticated attacker to access restore and administrator initialization endpoints within five minutes of starting an uninitialized instance. The attacker can restore a crafted backup or create the first administrator account, gaining full administrative access.

Risk Assessment

The risk is that an attacker on the network can gain full control over the container management platform, potentially compromising the confidentiality, integrity, and availability of managed container environments.

Recommendation

Immediately update Portainer Community Edition to version 2.39.4 or 2.43.0. If updating is not possible, restrict network access to the /api/restore and /api/users/admin/init endpoints during the setup window.

Other vulnerabilities in Portainer Community Edition

CVE-2026-44884Medium
In Portainer Community Edition from version 2.33.0 to before 2.33.8 and 2.39.1, a missing authorization vulnerability in the GET /api/custom_templates/{id}/file endpoint allows any authenticated user to read custom template files by enumerating sequential IDs. These files may contain sensitive data such as connection strings, API tokens, or registry credentials.

Original NVD description (English source)

Portainer Community Edition is a lightweight service delivery platform for containerized applications that can be used to manage Docker, Swarm, Kubernetes and ACI environments. In versions 2.39.0 through 2.39.3 and 2.40.0 until 2.43.0, unauthenticated restore and administrator initialization endpoints (/api/restore and /api/users/admin/init) remain accessible during the five-minute setup window for uninitialized instances, allowing a network attacker to restore a crafted backup or create the first administrator account and gain full administrative access. This issue is fixed in versions 2.39.4 and 2.43.0.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS