PT-2026-56482 · Portainer · Portainer

Published 2026-07-08 · Updated 2026-07-08 · CVE-2026-55761

Mitre

CVSS v4.0

7.1

High

Base vector

AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:H/SA:H

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.

Fix

Improper Authentication

Weakness Enumeration

CWE-287

Related Identifiers

CVE-2026-55761

Affected Products

Portainer

References · 7

• https://nvd.nist.gov/vuln/detail/CVE-2026-55761 · Security Note
• https://github.com/portainer/portainer/security/advisories/GHSA-x626-fcwx-f5pc · Note
• https://github.com/portainer/portainer/commit/49f19107cf9a3540cbe406c9eb7f24390e1af02b · Note
• https://github.com/portainer/portainer/commit/d2b56efcb4e43c4168bb6688eee9f6bf22867312 · Note
• https://github.com/portainer/portainer/releases/tag/2.43.0 · Note
• https://github.com/portainer/portainer/issues/2770 · Note
• https://github.com/portainer/portainer/releases/tag/2.39.4 · Note