CVE-2026-56296

Cap-go before 12.128.2 contains an information disclosure vulnerability in the public.transfer_app RPC function that returns distinct error messages for existing versus non-existing app IDs. Unauthenticated attackers can enumerate valid app IDs by observing error message differences when calling transfer_app with only the publishable API key.

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-fmm3-3qcg-85j6
https://www.vulncheck.com/advisories/cap-go-app-existence-oracle-via-unauthenticated-transfer-app-rpc
https://github.com/Cap-go/capgo/security/advisories/GHSA-fmm3-3qcg-85j6

Configurations

No configuration.

History

13 Jul 2026, 16:16

Type	Values Removed	Values Added
References	~~() https://github.com/Cap-go/capgo/security/advisories/GHSA-fmm3-3qcg-85j6 -~~	() https://github.com/Cap-go/capgo/security/advisories/GHSA-fmm3-3qcg-85j6 -

11 Jul 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-11 14:16

Updated : 2026-07-13 18:12

NVD link : CVE-2026-56296

Mitre link : CVE-2026-56296

CVE.ORG link : CVE-2026-56296

JSON object : View

Products Affected

No product.

CWE

CWE-203

Observable Discrepancy

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