CVE-2021-25369 is an improper access control vulnerability in Samsung Mobile Devices. CISA added it to the Known Exploited Vulnerabilities catalogue on 8 November 2022, which means attackers have used it in real attacks. Samsung mobile devices using Mali GPU contains an improper access control vulnerability in sec_log file. Exploitation of the vulnerability exposes sensitive kernel information to the userspace.
What this vulnerability means in a mobile device context
CVE-2021-25369 is an improper access control flaw in Samsung Mobile Devices, and the danger comes from access boundaries failing inside a component that handles sensitive device logging and kernel-adjacent data. When access control is wrong in a mobile platform, the issue is often less about crashing the device and more about exposing information that should never be available to ordinary apps or user-space processes.
Because CISA added the CVE to the KEV catalogue, organisations should treat it as a known exploited weakness rather than a theoretical hardening issue. That matters in mobile environments where unmanaged devices, delayed patching, and inconsistent fleet visibility can leave a vulnerable handset exposed long after public disclosure.
Why improper access control is dangerous here
The core risk in this class of flaw is that a low-privilege process can cross a boundary that was meant to protect sensitive operating-system internals. In this case, exposure of kernel information can reduce the attacker’s uncertainty about the device, its memory layout, or the state of security-relevant components, which can make follow-on exploitation easier.
That makes the vulnerability especially important in environments where mobile devices handle corporate email, authentication apps, secure messaging, or device-management enrolment. A flaw that reveals kernel information may not be a full compromise by itself, but it can strengthen an attacker’s position and undermine defensive assumptions about isolation between apps and the operating system.
How organisations assess exposure and reduce blast radius
Exposure checks should start with a complete inventory of Samsung mobile devices in service, including employee-owned devices that access work data. From there, teams should verify model, operating system build, management status, and whether the device is internet-reachable or enrolled in a mobile device management platform that enforces timely updates.
When patching is delayed, compensating controls should focus on limiting what a compromised device can reach. The most useful measures are tighter app allowlisting, stronger enrolment controls, reduced exposure to sensitive internal services, and segmentation of mobile access from higher-value administrative systems. The CIS Controls v8 and NIST Cybersecurity Framework 2.0 both support this kind of asset-driven exposure reduction.
Detection, validation, and post-exploitation review
Detection for this issue is usually indirect. Security teams should look for unexpected device behaviour, suspicious app activity, signs of mobile persistence, or evidence that an attacker has used the device as a stepping stone into internal services. The right posture is to treat the device as potentially exposed until it is confirmed patched and, where needed, re-enrolled or reset.
After remediation, review whether the device had access to sensitive credentials, tokens, or email sessions at the time of suspected exploitation. If there is any chance those identity materials were reachable from the compromised handset, rotate or revoke them as part of the incident response. For broader vulnerability-triage and remediation discipline, the Vulnerability Management Guide provides a useful operational model, and the NIST National Vulnerability Database and CVE Program remain the authoritative references for record and advisory tracking.
Risk and Threat Considerations
Improper access control in a mobile OS can be attractive to attackers because mobile devices often sit close to users, credentials, and corporate access paths. Even when the immediate effect is “only” information disclosure, that disclosure can help an attacker profile the device and prepare a deeper compromise.
Failure mechanism: A security boundary that should restrict access to kernel-related information fails, allowing user-space access to data that should stay protected.
Impact: Sensitive information leakage can support exploitation chaining, reduce attacker effort, and increase the chance that a mobile device becomes a trusted entry point into other systems.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
OWASP Non-Human Identity Top 10 addresses the attack and risk surface, while CIS Controls v8, NIST CSF 2.0 and NIST SP 800-53 Rev 5 set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| CIS Controls v8 | CIS-1 — Inventory and Control of Enterprise Assets | Mobile device exposure depends on knowing which Samsung devices exist and where they connect. |
| Recommendation — Maintain an accurate mobile asset inventory and flag vulnerable devices for containment. | ||
| NIST CSF 2.0 | ID.AM-01 — Physical devices and systems are inventoried | The term requires knowing whether affected devices are present in the environment. |
| Recommendation — Inventory Samsung devices so exposed models can be identified and prioritized. | ||
| NIST SP 800-53 Rev 5 | SI-2 — Flaw Remediation | This CVE is a known exploited flaw that requires tracked remediation and verification. |
| Recommendation — Prioritise remediation and verify the vulnerable device no longer exposes the flaw. | ||
| OWASP Non-Human Identity Top 10 | NHI-02 — Secret Leakage | Kernel information exposure can enable follow-on theft or misuse of identity material on mobile devices. |
| NHI-05 — Overprivileged NHI | Mobile access paths become more dangerous when devices or apps hold excessive trust. | |
| Recommendation — Treat exposed mobile secrets and sessions as compromised and rotate them promptly. Reduce device and app access so a compromised handset cannot reach excessive privileges. | ||
Practitioner Guidance
Why practitioners should care: For mobile fleets, the practical question is not whether the flaw is interesting, but whether vulnerable devices are still allowed to authenticate to business services. If they are, the exposure persists beyond the device itself.
Governance implication: Mobile patch compliance should be tied to access policy, not treated as a separate hygiene metric. When a device is behind on a known exploited CVE, its access should be constrained until it is remediated and verified.