CVE-2026-56338

Capgo before 12.128.2 contains a denial of service vulnerability in the /auth/v1/otp endpoint that prevents email verification for two-factor authentication due to captcha validation failures. Authenticated users cannot complete 2FA enrollment as the backend consistently returns HTTP 500 errors with captcha verification process failed messages, blocking access to security controls.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/Cap-go/capgo/security/advisories/GHSA-m53g-7gcj-x6f7
https://www.vulncheck.com/advisories/capgo-denial-of-service-in-2fa-email-verification-via-auth-v1-otp-endpoint
https://github.com/Cap-go/capgo/security/advisories/GHSA-m53g-7gcj-x6f7

Configurations

No configuration.

History

24 Jun 2026, 16:16

Type	Values Removed	Values Added
References	~~() https://github.com/Cap-go/capgo/security/advisories/GHSA-m53g-7gcj-x6f7 -~~	() https://github.com/Cap-go/capgo/security/advisories/GHSA-m53g-7gcj-x6f7 -

24 Jun 2026, 13:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-24 13:16

Updated : 2026-06-25 14:03

NVD link : CVE-2026-56338

Mitre link : CVE-2026-56338

CVE.ORG link : CVE-2026-56338

JSON object : View

Products Affected

No product.

CWE

CWE-703

Improper Check or Handling of Exceptional Conditions

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