Quick answers
- Is CVE-2026-44881 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-44881 being exploited in the wild.
- How severe is CVE-2026-44881?
- Critical severity, with a CVSS score of 9.9, published 28 May 2026.
- Which products and versions are affected?
- github.com/portainer/portainer (Go) SEMVER:introduced=0, SEMVER:introduced=2.33.0,fixed=2.33.8; Portainer >= 2.33.0, < 2.33.8; >= 2.39.0, < 2.39.2; >= 2.40.0, < 2.41.0; Portainer Community Edition 2.33.0 to < 2.33.8, 2.39.0 to < 2.39.2, 2.40.0 to < 2.41.0.
- Is there a fix for CVE-2026-44881?
- Yes. github.com/portainer/portainer (Go): upgrade to 2.33.8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-44881 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-44881?
- Check whether you run github.com/portainer/portainer (Go), Portainer or Portainer Community Edition at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- github.com/portainer/portainer (Go): upgrade to 2.33.8 or later
go get github.com/portainer/portainer@v2.33.8
Technical details
A vulnerability exists in Portainer's Git-backed stack deployment mechanism where the 'go-git' library translates Git symlink entries into real OS symlinks without validation. When Portainer's 'GET /api/stacks/{id}/file' endpoint reads the stack entry point (e.g., docker-compose.yml), it uses 'os.ReadFile', which transparently follows these symlinks to targets outside the intended worktree. An attacker with permissions to create or update stacks can point a symlink to sensitive files like '/etc/shadow' or Kubernetes service account tokens. The risk is heightened by the auto-update feature, which can trigger the file read automatically upon a malicious commit to the linked repository. Patches are available in versions 2.33.8, 2.39.2, and 2.41.0.
Affected products
- Portainer Portainer >= 2.33.0, < 2.33.8; >= 2.39.0, < 2.39.2; >= 2.40.0, < 2.41.0
Identifiers
- CVE-2026-44881
- GHSA-rpgq-m5fp-32wr
- GO-2026-5633
Timeline
- 2026-03-20: disclosed: Reported by b-hermes via GHSA
- 2026-04-18: patched: Fix merged to develop branch
- 2026-04-29: advisory: Version 2.41.0 released with fix
- 2026-05-07: advisory: Versions 2.33.8 and 2.39.2 released with fix
- 2026-05-14: advisory: Public advisory published