CVE-2019-2215 is an use-after-free vulnerability in Android Android Kernel. CISA added it to the Known Exploited Vulnerabilities catalogue on 3 November 2021, which means attackers have used it in real attacks. Android Kernel contains a use-after-free vulnerability in binder.c that allows for privilege escalation from an application to the Linux Kernel.
What a use-after-free means in a kernel vulnerability
A use-after-free happens when software keeps using memory after it has been released. In a kernel, that can turn a logic bug into memory corruption, because the freed object may be reused for something else before the stale reference is touched again.
That matters especially in privileged code. A kernel bug does not stay a simple crash if an attacker can influence timing, reuse patterns, or object layout, because the same flaw may be turned into controlled execution or privilege gain.
Why kernel use-after-free bugs are dangerous on Android
Android kernel vulnerabilities are particularly valuable to attackers because the kernel sits below apps and mediates core system privileges. A flaw in a path such as binder can let an app cross a trust boundary it should never be able to cross.
In this case, the primary concern is privilege escalation from an application into the Linux kernel. That kind of escalation can defeat app sandboxing, expose higher-value system state, and give an attacker a stronger foothold for persistence or follow-on exploitation.
Use-after-free issues are often security-relevant even when they begin as stability defects, because exploitation depends on what the freed object is used for and whether the attacker can shape memory reuse. The same underlying memory-safety weakness can therefore have very different impact depending on the surrounding kernel subsystem.
How organisations assess exposure to this CVE
Exposure review starts with a precise asset inventory, because the question is not whether an organisation uses Android somewhere, but whether the relevant devices, builds, or managed endpoints are running a vulnerable kernel lineage. Internet-facing mobile management surfaces and unmanaged fleet devices deserve particular attention.
Vendor advisories remain the authoritative source for affected builds and remediation specifics, while the NIST National Vulnerability Database and the CVE Program provide canonical record-level references for the vulnerability itself.
For prioritisation, the fact that CISA placed this issue in the Known Exploited Vulnerabilities catalogue means organisations should treat it as exposure with demonstrated real-world abuse, not as a purely theoretical kernel defect.
Remediation, detection, and post-compromise review
Where patching is available, remediation should be treated as a high-priority kernel update path rather than a routine maintenance item. If patching cannot happen immediately, temporary compensating controls should reduce attack surface by limiting device exposure, narrowing app install paths, and restricting risky execution contexts until the fix is deployed.
Detection is harder than prevention because kernel exploitation may leave few obvious application-level traces. Review device telemetry for abnormal crashes, privilege transitions, suspicious reboots, or signs that an attacker moved from application context into higher privilege.
After remediation, organisations should still review for post-patch compromise because successful exploitation may have already changed the device state. That review should focus on whether privileged access, tokens, or other sensitive material on the affected device could have been accessed after escalation.
For a broader vulnerability-handling lens, Vulnerability Management Guide helps frame asset scoping, prioritisation, verification, and exception handling, while CWE Top 25 Guide is useful context for why use-after-free remains a persistent memory-safety class.
Risk and Threat Considerations
Kernel use-after-free flaws are attractive to attackers because they can convert a memory-safety bug into privilege escalation, code execution, or deeper device control. On mobile systems, that can undermine the boundary between an untrusted app and trusted operating-system functions.
Failure mechanism: The attacker triggers the stale reference after the freed kernel object has been reused, then shapes the new contents or access pattern so the kernel performs an unintended privileged operation.
Impact: Successful exploitation can grant kernel-level authority, defeat sandboxing, and expose the device to data theft, persistence, or additional malware installation.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
NIST SP 800-53 Rev 5 and CIS Controls v8 set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| NIST SP 800-53 Rev 5 | SI-2 — Flaw Remediation | Kernel use-after-free issues require prioritized remediation and verification. |
| IR-4 — Incident Handling | Real-world exploitation requires post-patch compromise review and response actions. | |
| RA-5 — Vulnerability Monitoring and Scanning | Exposure assessment depends on inventory and monitoring for vulnerable Android builds. | |
| Recommendation — Prioritize kernel updates, validate deployment, and track remediation exceptions until the flaw is closed. Investigate suspected exploitation, preserve evidence, and confirm whether the device was compromised before remediation. Continuously identify vulnerable devices, confirm affected builds, and prioritize remediation based on exposure. | ||
| CIS Controls v8 | CIS-7 — Continuous Vulnerability Management | Actively exploited CVEs should be found, prioritized, and remediated quickly. |
| CIS-8 — Audit Log Management | Post-exploitation review depends on usable logs and telemetry for compromise indicators. | |
| Recommendation — Continuously inventory devices, prioritize exploited kernel flaws, and verify remediation completion. Collect and retain device telemetry to support detection and retrospective compromise review. | ||
Practitioner Guidance
What to watch for: Treat any Android fleet that cannot be rapidly updated as a higher-risk population, especially where devices are exposed to untrusted apps or operate outside tight mobile management controls. Kernel issues should be triaged by exploitability and business exposure, not only by the visible severity label.
Practitioner takeaway: For KEV-listed kernel flaws, the right operating assumption is that exposure exists until you have confirmed the affected build is remediated and the device has been reviewed for compromise.
Related resources from NHI Mgmt Group
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Reviewed and updated by the NHIMG editorial team on October 17, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org