CVE-2026-56296

MEDIUM

Cap-go - App Existence Oracle via Unauthenticated transfer_app RPC

Title source: cna
STIX 2.1

Description

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.

References (2)

Core 2
Core References
Vendor Advisory vendor-advisory
GitHub Security Advisory (GHSA-fmm3-3qcg-85j6)
https://github.com/Cap-go/capgo/security/advisories/GHSA-fmm3-3qcg-85j6
Third Party Advisory third-party-advisory
VulnCheck Advisory: Cap-go - App Existence Oracle via Unauthenticated transfer_app RPC
https://www.vulncheck.com/advisories/cap-go-app-existence-oracle-via-unauthenticated-transfer-app-rpc

Scores

CVSS v3 5.3
EPSS 0.0024
EPSS Percentile 15.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

CWE
CWE-203
Status published
Products (2)
Cap-go/capgo < 12.128.2
Cap-go/capgo 12.128.2
Published Jul 11, 2026
Tracked Since Jul 11, 2026