---
id: CVE-2026-56223
title: >-
  Capgo before 12.128.2 contains a cross-domain SSO account takeover
  vulnerability in the provision-user endpoint that allows attackers to merge
  arbitrary victim accounts based on email match without validating SSO provider
  domain authoriz…
summary: >-
  Capgo before 12.128.2 contains a cross-domain SSO account takeover
  vulnerability in the provision-user endpoint that allows attackers to merge
  arbitrary victim accounts based on email match without validating SSO provider
  domain authoriz…
severity: high
cvss: 8.7
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N'
cwe:
  - CWE-287
vendor: Capgo
product: Capgo
affected:
  - Capgo < 12.128.2
published: '2026-06-24'
updated: '2026-09-17'
sourceUpdated: '2026-09-17T18:16:49.943'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-56223'
references:
  - url: 'https://github.com/Cap-go/capgo/security/advisories/GHSA-jhjh-vp9p-54fg'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/capgo-account-takeover-via-cross-domain-sso-email-assertion-in-provision-user
    label: disclosure@vulncheck.com
  - url: 'https://github.com/Cap-go/capgo/security/advisories/GHSA-jhjh-vp9p-54fg'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-06-24T13:45:44.261860Z'
epss: 0.00402
epssPercentile: 0.31739
ingestedAt: '2026-09-17T18:25:15.973Z'
---

## Overview

Capgo before 12.128.2 contains a cross-domain SSO account takeover vulnerability in the provision-user endpoint that allows attackers to merge arbitrary victim accounts based on email match without validating SSO provider domain authorization. An attacker with enterprise org admin access and a malicious IdP can forge SAML assertions containing victim email addresses to trigger account merge and gain full access to victim accounts, organizations, and data.

## Remediation

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