Auth bypass in Capgo
CVE-2026-56237
Capgo before 12.128.2 contains a broken authentication vulnerability in its API key generation mechanism. API keys are exposed in frontend requests, and the backend fails to validate that keys are securely generated and bound to the authenticated user. An attacker can tamper with the API key parameter in the generation request and supply arbitrary values, generating custom API keys without proper authorization, which can lead to unauthorized access to protected endpoints.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.005 (41.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 41.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Capgo — versions 0, 12.128.2
Weakness classification (CWE)
References
- github.com/Cap-go/capgo/security/advisories/GHSA-22w2-mx2h-4fr7 (vendor-advisory)
- www.vulncheck.com/advisories/capgo-unauthenticated-api-key-generation-via-clien… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-56237?
- CVE-2026-56237 is a critical-severity vulnerability in Capgo, classified under Improper Authentication. CVSS score: 9.1/10. Published 2026-06-24.
- How severe is CVE-2026-56237?
- Critical severity. CVSS v3 base score is 9.1 out of 10.