CVE-2026-56316

Cap-go before 12.128.2 contains an information disclosure vulnerability in the OPTIONS /build/upload/:jobId/* endpoint that allows unauthenticated attackers to enumerate valid builder job IDs through observable response discrepancies. Attackers can probe the endpoint without authentication to distinguish valid job IDs from invalid ones and generate sustained unauthenticated traffic for resource consumption.

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 LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/Cap-go/capgo/security/advisories/GHSA-9c2x-7h5x-37gm
https://www.vulncheck.com/advisories/cap-go-job-existence-oracle-via-unauthenticated-options-build-upload-jobid

Configurations

No configuration.

History

21 Jun 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-21 14:16

Updated : 2026-06-22 18:41

NVD link : CVE-2026-56316

Mitre link : CVE-2026-56316

CVE.ORG link : CVE-2026-56316

JSON object : View

Products Affected

No product.

CWE

CWE-203

Observable Discrepancy

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