CVE-2026-56299

Capgo before 12.128.2 contains an authentication bypass vulnerability in the /build/upload/:jobId/* endpoint that allows unauthenticated attackers to trigger consistent 500 errors. Remote attackers can send OPTIONS requests to bypass authentication middleware and invoke tusProxy logic with invalid credentials, enabling trivial request flooding and denial of service.

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-6c7m-4223-446j
https://www.vulncheck.com/advisories/capgo-denial-of-service-via-unauthenticated-options-request-to-build-upload-endpoint

Configurations

No configuration.

History

21 Jun 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-21 14:16

Updated : 2026-06-23 15:16

NVD link : CVE-2026-56299

Mitre link : CVE-2026-56299

CVE.ORG link : CVE-2026-56299

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

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