---
id: CVE-2026-100629
title: >-
  Capgo (capgo.app backend) before 12.127.5 contains an authorization flaw in
  the PATCH /private/role_bindings/:binding_id endpoint
summary: >-
  Capgo (capgo.app backend) before 12.127.5 contains an authorization flaw in
  the PATCH /private/role_bindings/:binding_id endpoint. The handler verifies
  that the newly assigned role's priority rank does not exceed the caller's own
  rank, b…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:L'
cwe:
  - CWE-863
vendor: Cap-go
product: capgo.app
affected:
  - capgo.app < 12.127.5
published: '2026-09-26'
updated: '2026-09-26'
sourceUpdated: '2026-09-26T14:16:44.117'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100629'
references:
  - url: >-
      https://github.com/Cap-go/capgo.app/security/advisories/GHSA-54mj-q77q-xwx5
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/capgo-backend-before-12.127.5-privilege-escalation-via-role-bindings-patch
    label: disclosure@vulncheck.com
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-26T13:33:20.928Z'
---

## Overview

Capgo (capgo.app backend) before 12.127.5 contains an authorization flaw in the PATCH /private/role_bindings/:binding_id endpoint. The handler verifies that the newly assigned role's priority rank does not exceed the caller's own rank, but — unlike the DELETE handler — it never checks the rank of the role currently bound to the target binding. An authenticated user holding the org_admin role (rank 90) can therefore change an org_super_admin binding (rank 95) to a lower-privileged role such as org_member (rank 75). Because the prevent_last_super_admin_binding_delete database trigger fires only BEFORE DELETE and not on UPDATE, an org_admin can demote every org_super_admin, leaving the organization with no super administrator. The issue is fixed in 12.127.5.

## Remediation

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