CVE-2026-49311 in HarmonyOS
Summary
by MITRE • 09/09/2026
Permission control vulnerability in the event notification module.Impact: Successful exploitation of this vulnerability may affect availability.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 09/09/2026
The identified security flaw resides within the event notification subsystem of the application, specifically manifesting as a permission control deficiency that undermines the integrity of access enforcement mechanisms. This type of vulnerability typically arises when the system fails to adequately verify whether an authenticated user possesses the requisite privileges before processing or delivering notifications intended for specific roles or administrative functions. In many enterprise architectures, the event notification module serves as a critical communication channel between backend services and end-users, often handling sensitive operational alerts, security warnings, or configuration changes. When permission checks are bypassed or improperly implemented within this layer, it allows unauthorized entities to interact with components that should be restricted, leading to potential disruptions in service availability rather than direct data exfiltration or privilege escalation.
From a technical perspective, the core issue involves an insecure direct object reference or broken access control logic where the application relies on client-side validation or insufficient server-side checks regarding user roles and permissions. An attacker who has obtained valid credentials for a low-privilege account can manipulate request parameters to trigger notification events that are intended for higher-level administrators or system processes. This manipulation may involve crafting specific HTTP requests with altered identifiers, tokens, or payload structures that trick the backend into executing privileged operations or broadcasting sensitive information to unintended recipients. The lack of rigorous authorization checks at the point where notifications are generated and dispatched creates a gap in the defense-in-depth strategy, allowing malicious actors to exploit this trust relationship between the user interface and the notification engine.
The operational impact of exploiting this vulnerability is primarily centered on availability degradation rather than confidentiality or integrity breaches in the traditional sense. By triggering excessive or malformed event notifications, an attacker can induce resource exhaustion conditions such as memory leaks, CPU spikes, or database connection pool saturation within the application server. This denial-of-service effect disrupts normal business operations by rendering the system unresponsive to legitimate users and administrators who rely on timely and accurate alerts for incident response and monitoring. Furthermore, if the notification module integrates with external communication channels like email gateways or SMS providers, abuse of this vulnerability could lead to rate limiting penalties from third-party services, further compounding service disruption costs and operational inefficiencies.
This flaw aligns closely with CWE-269 Improper Privilege Management and CWE-862 Missing Authorization, as the root cause is a failure to enforce proper access controls on sensitive functions within the notification module. In terms of offensive security frameworks, this vulnerability maps to MITRE ATT&CK technique T1078 Valid Accounts, where attackers leverage legitimate credentials to perform unauthorized actions due to insufficient privilege separation. It also relates to T1496 Resource Hijacking if the exploitation leads to significant resource consumption affecting system performance. Understanding these mappings is crucial for categorizing the risk accurately and prioritizing remediation efforts within a broader vulnerability management program that adheres to industry best practices for application security.
To mitigate this vulnerability, developers must implement robust server-side authorization checks at every entry point of the event notification module, ensuring that each request is validated against the user's assigned roles and permissions before any processing occurs. It is essential to adopt a principle of least privilege by restricting access to administrative notification functions exclusively to users with explicit admin rights. Additionally, implementing rate limiting and input validation on all parameters passed to the notification service can help prevent abuse attempts that lead to resource exhaustion. Security testing should include rigorous penetration tests focused on horizontal and vertical privilege escalation scenarios within the messaging subsystem. Regular code reviews emphasizing secure coding standards for access control logic will further reduce the likelihood of similar flaws emerging in future development cycles, thereby strengthening the overall resilience of the application against availability-focused attacks.