Capgo - Denial of Service in 2FA Email Verification via /auth/v1/otp Endpoint
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · Low
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA Capgo (Capgo) Fixed in 12.128.2
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
Capgo 12.128.2
10 records Highest priority Priority HIGH 7 HIGH, 3 MEDIUM
Other records, highest priority first
- TI-2026-40602 Capgo - Unauthenticated API Key Generation via Client-Side Parameter ManipulationPriority HIGH 81
- TI-2026-40597 Capgo - Subkey Scope Bypass in middlewareKey via x-limited-key-id HeaderPriority HIGH 73
- TI-2026-40588 Capgo - Account Takeover via Cross-Domain SSO Email Assertion in provision-userPriority HIGH 73
Timeline
- 2026-10-02 Threatist record created from CVE-2026-56338
References
More Capgo vulnerabilities
- TI-2026-40602 Capgo - Unauthenticated API Key Generation via Client-Side Parameter Manipulation CVSS 4.0CRITICAL 9.3
- TI-2026-40473 Cap-go - Account Lockout via 2FA Misconfiguration on Unverified Email CVSS 4.0CRITICAL 9.3
- TI-2026-40465 Cap-go - OTP Bypass via Response Manipulation in Email Verification CVSS 4.0CRITICAL 9.3
- TI-2026-64782 capgo.app through 12.129.0 Cache Restoration of Deleted Bundles CVSS 4.0HIGH 8.7
- TI-2026-40704 Capgo - Unauthenticated Organization Existence Enumeration via rescind_invitation RPC CVSS 4.0HIGH 8.7
- TI-2026-40689 Capgo - Rate Limit Bypass via User-Controlled device_id Parameter CVSS 4.0HIGH 8.8
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences