CVE-2026-44881
CriticalCVSS 9.9Exploitation Probability (EPSS)
Low risk34th percentile - higher than 34% of all known CVEs
Summary
Portainer Community Edition from version 2.33.0 to 2.33.8, 2.39.2, and 2.41.0 contains a vulnerability where, during creation or update of Git-backed stacks, go-git v5 creates OS symlinks on the host filesystem without validation, except for .gitmodules. An authenticated user with rights to manage Git stacks can include a docker-compose.yml file as a symlink to an arbitrary path, causing the GET /api/stacks/{id}/file endpoint to read and return the symlink target's contents in the HTTP response.
Risk Assessment
The risk is that an authenticated user can read arbitrary files accessible to the Portainer process, potentially leading to exposure of sensitive data such as configurations, passwords, or access keys.
Recommendation
Immediately update Portainer CE to version 2.33.8, 2.39.2, or 2.41.0, which contain the fix for this vulnerability.
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. From 2.33.0 to before 2.33.8, 2.39.2, and 2.41.0, Portainer supports deploying stacks from Git repositories. When a Git-backed stack is created or updated, Portainer clones the repository using go-git v5, which translates Git blob entries with mode 0o120000 (symlink) into real OS symlinks on the host filesystem via os.Symlink. The only entry blocked from becoming a symlink is .gitmodules; every other path is created as a symlink without validation. Portainer's GET /api/stacks/{id}/file endpoint then reads the stack entry point with os.ReadFile, which follows OS symlinks transparently. A repository containing docker-compose.yml as a symlink to an arbitrary filesystem path causes the symlink target's contents to be returned verbatim in the HTTP response. Any authenticated user with rights to create or update a Git-backed stack — the default configuration in Portainer CE — can read arbitrary files accessible to the Portainer process. This vulnerability is fixed in 2.33.8, 2.39.2, and 2.41.0.