CVE-2026-49089 in Kibana
Summary
by MITRE • 08/13/2026
Allocation of Resources Without Limits or Throttling (CWE-770) in Kibana can lead to denial of service via Excessive Allocation (CAPEC-130). A query expression accepted by a connector reporting operation was processed without any limit on its size, and an oversized expression caused the Kibana process to spend an unbounded amount of time evaluating it. An authenticated user with read-only privileges was able to send a single request that left Kibana unable to serve any user until the process was restarted.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 08/13/2026
The vulnerability described represents a critical resource allocation flaw that fundamentally undermines system availability and operational integrity within the Kibana platform. This issue manifests as an improper handling of query expressions during connector reporting operations where the system fails to implement any form of size limitation or throttling mechanism. The absence of resource constraints allows malicious or malformed queries to consume excessive computational resources, leading to a complete denial of service condition that affects all users of the platform.
This vulnerability directly maps to CWE-770 which categorizes improper resource management as a fundamental security weakness where systems fail to properly allocate and limit resource consumption. The flaw operates at the intersection of insufficient input validation and inadequate system throttling mechanisms, creating an environment where a single malicious request can cascade into system-wide unresponsiveness. The specific operational context involves authenticated users with read-only privileges, which demonstrates how even seemingly limited user access can be exploited to cause significant disruption when combined with poorly controlled resource allocation.
The impact of this vulnerability extends beyond simple performance degradation to complete service interruption, as evidenced by the requirement for process restart to restore normal operations. When an oversized query expression is processed without size limits, the Kibana process becomes trapped in an unbounded evaluation loop consuming CPU resources and memory until manual intervention occurs. This behavior aligns with CAPEC-130's description of excessive allocation attacks where resource consumption grows without bounds, ultimately exhausting system capabilities and rendering the service unavailable to legitimate users.
From an operational standpoint, this vulnerability creates a particularly dangerous scenario for production environments where Kibana serves as a critical monitoring and analytics platform. The fact that read-only privileges are sufficient to trigger this condition suggests a fundamental flaw in privilege-based access controls and resource management policies. Attackers could potentially exploit this weakness repeatedly without requiring elevated permissions, making it an attractive target for persistent denial of service attacks.
Mitigation strategies should focus on implementing comprehensive input validation and resource limiting mechanisms throughout the Kibana query processing pipeline. The system must establish hard limits on query expression sizes and implement proper throttling controls to prevent any single request from consuming disproportionate system resources. Additionally, monitoring and alerting systems should be deployed to detect unusual resource consumption patterns that may indicate exploitation attempts. Organizations should also consider implementing rate limiting at multiple levels including network, application, and database access controls to provide layered protection against similar vulnerabilities. The remediation process must include thorough testing of resource limits and validation of query processing behavior under various load conditions to ensure the effectiveness of implemented controls.
This vulnerability exemplifies how seemingly simple resource management oversight can result in catastrophic system availability failures, emphasizing the importance of robust input validation and resource control mechanisms as outlined in industry best practices for secure system design and development.