CVE-2019-20146 in Community Edition
Summary
by MITRE
An issue was discovered in GitLab Community Edition (CE) and Enterprise Edition (EE) 11.0 through 12.6. It allows Uncontrolled Resource Consumption.
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Analysis
by VulDB Data Team • 01/14/2020
The vulnerability identified as CVE-2019-20146 represents a significant resource consumption flaw affecting GitLab Community Edition and Enterprise Edition versions ranging from 11.0 to 12.6. This issue falls under the broader category of resource exhaustion vulnerabilities that can severely impact system availability and performance. The flaw manifests when certain operations within the GitLab platform consume excessive computational resources without proper bounds or limitations, potentially leading to system degradation or complete service unavailability.
Technical exploitation of this vulnerability occurs through specific GitLab functionalities that process user inputs or repository operations without adequate resource monitoring mechanisms. The flaw typically involves operations that involve parsing, processing, or analyzing large datasets or complex repository structures where the system fails to implement proper resource consumption limits. This allows attackers to craft malicious inputs or perform specific sequences of operations that cause the GitLab instance to consume disproportionate amounts of CPU cycles, memory, or disk I/O resources. The vulnerability is particularly concerning because it can be triggered through legitimate user interactions or automated scripts without requiring special privileges or authentication.
The operational impact of CVE-2019-20146 extends beyond simple performance degradation to potentially cause complete system outages or service disruption for GitLab instances. When exploited, the vulnerability can lead to denial of service conditions where legitimate users cannot access the platform due to resource exhaustion. The attack surface is broad as it affects multiple versions of GitLab across both community and enterprise editions, making it a widespread concern for organizations using these platforms. System administrators may observe unusual resource utilization patterns, increased latency in response times, or complete service failures during exploitation attempts. The vulnerability can also impact backup operations, repository synchronization, and other routine GitLab functions that rely on proper resource management.
Organizations affected by this vulnerability should immediately implement mitigations including updating to patched versions of GitLab where available, implementing resource limits and monitoring for affected operations, and establishing proper input validation and sanitization measures. The vulnerability aligns with CWE-400 which categorizes issues related to uncontrolled resource consumption and represents a classic example of how insufficient resource management can lead to denial of service conditions. From an attack perspective, this vulnerability maps to several ATT&CK techniques including resource exhaustion and service disruption methods. Security teams should also consider implementing rate limiting mechanisms, monitoring for unusual resource consumption patterns, and establishing incident response procedures specifically addressing resource exhaustion attacks. The remediation process requires careful attention to ensure that patches do not introduce compatibility issues with existing GitLab configurations or custom integrations that organizations may have implemented.