Samsung CmcCore CVE-2026-21121

Requires local code execution on the affected Samsung device - typically a malicious or sideloaded application running on the handset - before SMR Oct-2026 Release 1 is applied. The specific condition is that CmcCore exposes privileged APIs while failing to enforce sufficient permission checks, so any local process can call those APIs to obtain information normally restricted. Limiting factors: exploitation is strictly local (AV:L), cannot be performed remotely or over a network, and is confined to devices running vulnerable firmware prior to the October 2026 security maintenance release; impact is limited to information disclosure (no integrity or availability effect).

This is a moderate-risk local privilege/permission flaw in Samsung's CmcCore component, not a remote-exploitable priority. The provided CVSS 4.0 vector (AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N) describes a local attack with low complexity and no privileges required, yielding high confidentiality impact only (no integrity or availability impact), consistent with the 'Information Disclosure' tag and the description's reference to improper permission handling exposing privileged APIs. The 6.9 base score reflects the local attack vector capping real-world exposure: an attacker must already be able to run code on the device (e.g., a malicious or sideloaded app). No EPSS score, no CISA KEV listing, and no POC were provided in the input, so there is no public exploit identified at time of analysis and no evidence of active exploitation. Signals are internally consistent - there is no conflict between the CVSS vector and the description - but note the input supplies only a CVSS 4.0 vector (no 3.1 vector) and no CWE, so the exact weakness class is inferred from the wording ('improper handling of insufficient permission'). Overall: a legitimate issue worth patching via the SMR Oct-2026 Release 1 update, but a local-only, high-CVSS-but-bounded-real-risk issue rather than an emergency.

A malicious or low-privileged application installed on a Samsung device locally invokes CmcCore's privileged APIs, which fail to properly enforce permission checks, allowing the app to read sensitive information it should not have access to. No user interaction or prior authentication is required per the CVSS vector, but physical or logical local access (code execution on the device) is a prerequisite. No public exploit code was identified in the provided data.