---
id: "CVE-2026-104949"
kind: "vulnerability"
aliases: ["CVE-2026-104949"]
title: "WarehousePG: missing privilege check lets low-privileged users add fake standby"
severity: "low"
cvss: 2.3
epss: 0.00216
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["data-warehouse", "package", "postgres", "self-hosted", "warehousepg"]
not_affected_if: ["default-config", "superuser-only-access"]
published_at: "2026-10-21T14:17:09+00:00"
first_seen_at: "2026-10-23T21:57:28+00:00"
updated_at: "2026-10-25T04:49:46+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-104949", "first_seen_at": "2026-10-23T21:57:28+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-104949", "first_seen_at": "2026-10-24T13:15:54+00:00"}]
---

# WarehousePG: missing privilege check lets low-privileged users add fake standby

WarehousePG's gp_add_coordinator_standby() function, also named gp_add_master_standby(), does not require superuser rights, so a low-privileged user with a utility-mode connection can insert a fake standby coordinator entry into gp_segment_configuration. The fake entry blocks administrators from adding a real standby until a superuser removes it, and user data is not exposed or modified.

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

## How to check

- Run `SELECT version();` in the WarehousePG database to confirm whether the release is in `6.27.1` through `6.27.6` or `7.2.1` through `7.6.0`.
- Check whether the cluster has a standby coordinator configured, and look for unexpected standby rows in `gp_segment_configuration`.
- Review which roles can open utility-mode connections.

## Fix

- Upgrade WarehousePG 6 past `6.27.6` or WarehousePG 7 past `7.6.0` to a fixed release (the fixed version is unknown from the sources).
- Remove any fake standby entry from `gp_segment_configuration` with a superuser account after upgrading.

## Timeline

- 2026-10-23T21:57:28+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-104949
- 2026-10-24T13:15:54+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-104949

## From the sources

WarehousePG (WHPG) 6.27.1 through 6.27.6 and 7.2.1 through 7.6.0 are affected by a missing authorization vulnerability (CWE-862) in gp_add_coordinator_standby(). The function is named gp_add_master_standby() in WHPG 6, and WHPG 7 keeps that name as an alias. Unlike the other segment add and remove functions, it does not require superuser privileges. A low-privileged user who can open a utility-mode connection can use it to add a fake standby coordinator entry to gp_segment_configuration on a cluster that has no standby configured. Administrators then cannot add a real standby until a superuser removes the fake entry. User data is not exposed or modified.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_