Vulnerability · Published Jun 24, 2026 · Assigned by VulnCheck

CVE-2026-56237Capgo - Unauthenticated API Key Generation via Client-Side Parameter Manipulation

Critical 9.1

In plain English

A critical-severity improper authentication in Capgo from Capgo. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities).

Severity (CVSS 3.1)9.1Critical

Exploit odds (30 days)0.5%top 55.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
Capgo	Capgo	0 – before 12.128.2

Weakness: CWE-287 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

References

GitHub Security Advisory (GHSA-22w2-mx2h-4fr7) vendor-advisory
VulnCheck Advisory: Capgo - Unauthenticated API Key Generation via Client-Side Parameter Manipulation third-party-advisory