CVE-2026-56252: Capgo - Scope Isolation Failure in Webhook Test Endpoint

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-12 · updated 2026-10-25
Weakness: CWE-863

Description

Capgo before 12.128.2 contains a scope isolation vulnerability in the POST /webhooks/test endpoint that allows app-scoped API keys to invoke org-scoped webhook operations. Attackers with app-scoped credentials can trigger signed outbound webhook deliveries for arbitrary organization webhooks outside their declared app boundary, bypassing the limited_to_apps authorization check.

Affected products

Capgo: before 12.128.2 — fixed in 12.128.2

How to fix

Upgrade to a fixed version: Capgo 12.128.2. Check the vendor advisory for mitigations.

References

https://github.com/Cap-go/capgo/security/advisories/GHSA-qvr7-f6j6-64wp
https://www.vulncheck.com/advisories/capgo-scope-isolation-failure-in-webhook-test-endpoint
https://github.com/Cap-go/capgo/security/advisories/GHSA-qvr7-f6j6-64wp

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