CVE-2026-88864

Capgo (capgo.app) fails to restrict direct write access to the public.sso_providers table exposed through Supabase PostgREST. A holder of an ordinary Capgo full API key can insert a row with status='active' and enforce_sso=true, bypassing the intended backend SSO provisioning route (supabase/functions/_backend/private/sso/providers.ts) and its controls: the Enterprise plan requirement, SSO provider creation via the Supabase Management API, DNS TXT domain-ownership verification, the pending_verification → verified → active status transition, and issuance of a trusted provider ID by Supabase Auth. The forged row is trusted by SSO discovery and enforcement logic, including the unauthenticated login preflight endpoint /private/sso/check-domain, which then reports {"has_sso": true, "enforce_sso": true} for domains that were never verified, allowing attacker-controlled SSO enforcement to be asserted for arbitrary domains and disrupting normal login. All versions are affected; at the time of the advisory no patch was available.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.1 / Impact : 5.3

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact HIGH

Availability Impact LOW

Scope CHANGED

References

Link	Resource
https://github.com/Cap-go/capgo.app/security/advisories/GHSA-xg7v-83qv-qfff
https://www.vulncheck.com/advisories/capgo-sso-provider-authentication-bypass-via-postgrest-direct-write
https://github.com/Cap-go/capgo.app/security/advisories/GHSA-xg7v-83qv-qfff

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-10 14:17

Updated : 2026-09-10 15:17

NVD link : CVE-2026-88864

Mitre link : CVE-2026-88864

CVE.ORG link : CVE-2026-88864

JSON object : View

Products Affected

No product.

CWE

CWE-284

Improper Access Control

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