---
id: "CVE-2026-127081"
page: "https://infrastack.ai/live/CVE-2026-127081"
kind: "vulnerability"
aliases: ["CVE-2026-127081"]
title: "OpsTree BuildPiper: authenticated users can link stages to other projects' environments"
severity: "medium"
cvss: 5.3
epss: null
exploited: false
status: "open"
category: "other"
products: []
ecosystems: []
tags: ["buildpiper", "ci-cd", "other", "self-hosted"]
not_affected_if: ["single-project", "trusted-users-only"]
published_at: "2026-11-13T10:18:04+00:00"
first_seen_at: "2026-11-13T10:47:29+00:00"
updated_at: "2026-11-13T10:57:06+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-127081", "first_seen_at": "2026-11-13T10:47:29+00:00"}]
exploit_sources: []
---

# OpsTree BuildPiper: authenticated users can link stages to other projects' environments

Link for people: https://infrastack.ai/live/CVE-2026-127081 (this .md is for agents)

OpsTree BuildPiper before 2.7.0 lets a logged-in user attach pipeline stages to environments belonging to other projects by sending a foreign project_env_id to the stages endpoint. The cross-project links persist and break the separation between projects.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed BuildPiper version; unknown if the sources give the exact command.
- Review whether the pipeline stages API (POST /api/v1/pipeline/{pipeline_id}/stages/) is reachable by non-admin users.

## Fix

- Move to BuildPiper `2.7.0` or later.

## Timeline

- 2026-11-13T10:47:29+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-127081

## Documents

- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/opstree-buildpiper-before-2.7.0-authorization-bypass-via-pipeline-stage-project-env-id

## From the sources

OpsTree BuildPiper before 2.7.0 contains an authorization bypass vulnerability that allows authenticated users to link pipeline stages to environments of other projects by supplying a foreign project_env_id. Attackers can submit another project's environment identifier to the POST /api/v1/pipeline/{pipeline_id}/stages/ endpoint, persisting cross-project associations that bypass project separation.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_