CVE-2026-55761CWE-287

Portainer: Unauthenticated Restore Endpoint Allows Admin Takeover on Uninitialised Portainer Instances

High · published July 8, 2026

CVSS v4.0
7.1
EPSS
0%
Percentile
41.4
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
7.1 · HIGH
Vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:H/SA:H
EPSS
0.00493 · 41.4th percentile
Weakness
CWE-287 · Improper Authentication
Published
2026-07-08T15:03Z
EPSS history
Timeline
  • 08 JUL 15:03Z
    Portainer: Unauthenticated Restore Endpoint Allows Admin Takeover on Uninitialised Portainer Instances
    cvelistv5