---
id: CVE-2026-44300
title: OpenCost provides cost monitoring for Kubernetes workloads and cloud costs
summary: >-
  OpenCost provides cost monitoring for Kubernetes workloads and cloud costs.
  Prior to 1.121.0, the POST /serviceKey endpoint in pkg/costmodel/router.go
  allows a network client to invoke AddServiceKey without mandatory
  authentication and s…
severity: high
cvss: 8.8
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N'
cwe:
  - CWE-20
  - CWE-309
vendor: opencost
product: opencost
affected:
  - opencost < 1.121.0
patched:
  - github.com/opencost/opencost 1.119.1
published: '2026-09-15'
updated: '2026-09-15'
sourceUpdated: '2026-09-15T20:17:15.993'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-44300'
references:
  - url: >-
      https://github.com/opencost/opencost/commit/69430e7f627b3e62c8999312c06949267fab813a
    label: security-advisories@github.com
  - url: >-
      https://github.com/opencost/opencost/commit/a49a25bc2e0d6e220a131a4dc58f38ebe6ae851b
    label: security-advisories@github.com
  - url: 'https://github.com/opencost/opencost/pull/3651'
    label: security-advisories@github.com
  - url: 'https://github.com/opencost/opencost/pull/3910'
    label: security-advisories@github.com
  - url: 'https://github.com/opencost/opencost/releases/tag/v1.120.0'
    label: security-advisories@github.com
  - url: 'https://github.com/opencost/opencost/releases/tag/v1.121.0'
    label: security-advisories@github.com
  - url: >-
      https://github.com/opencost/opencost/security/advisories/GHSA-wmj8-9953-vff5
    label: security-advisories@github.com
  - url: 'https://github.com/advisories/GHSA-wmj8-9953-vff5'
tags:
  - nvd
  - cve.org
  - ghsa
  - go
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-09-15T19:16:35.644735Z'
cvssSource: cna
aliases:
  - GHSA-wmj8-9953-vff5
ecosystem: go
ingestedAt: '2026-07-14T17:37:27.702Z'
epss: 0.00753
epssPercentile: 0.53096
---

## Overview

OpenCost provides cost monitoring for Kubernetes workloads and cloud costs. Prior to 1.121.0, the POST /serviceKey endpoint in pkg/costmodel/router.go allows a network client to invoke AddServiceKey without mandatory authentication and submit an arbitrary key form value that is written to the GCP service-account key.json file returned by GetGCPAuthSecretFilePath in core/pkg/env/core.go. The attacker controls the file contents but not the CONFIG_PATH-derived directory, the key.json filename, or the file mode. Replacing the credential contents can disrupt GCP cost collection or cause OpenCost to use attacker-selected credentials, and the wildcard Access-Control-Allow-Origin response permits browser-assisted requests when the service is reachable from a browser. This issue is fixed in version 1.121.0.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-44300)

Affected packages:

- `github.com/opencost/opencost < 1.119.1`

Patched in:

- `github.com/opencost/opencost 1.119.1`

Source: https://github.com/advisories/GHSA-wmj8-9953-vff5