CVE-2020-13273 in Community Edition
Summary
by MITRE
A Denial of Service vulnerability allowed exhausting the system resources in GitLab CE/EE 12.0 and later through 13.0.1
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Analysis
by VulDB Data Team • 10/26/2020
The vulnerability identified as CVE-2020-13273 represents a critical denial of service weakness affecting GitLab Community Edition and Enterprise Edition versions from 12.0 through 13.0.1. This flaw resides within the GitLab application's resource management mechanisms and allows malicious actors to consume excessive system resources through carefully crafted requests. The vulnerability stems from inadequate input validation and resource allocation controls within the application's processing pipeline, specifically targeting how the system handles certain repository operations and user interactions. Attackers can exploit this weakness by submitting specially constructed requests that trigger resource-intensive operations without proper bounds checking or resource limiting mechanisms.
The technical implementation of this vulnerability involves the manipulation of GitLab's internal processing workflows where legitimate user operations can be transformed into resource exhaustion attacks. When a vulnerable GitLab instance receives malicious input, the system begins to allocate memory and processing power to handle these requests without sufficient safeguards against excessive resource consumption. This particular flaw operates at the application level rather than at the network or infrastructure layer, making it particularly dangerous as it can be exploited through normal application interfaces. The vulnerability can be classified under CWE-400 as an Uncontrolled Resource Consumption weakness, specifically manifesting as a resource leak or exhaustion scenario where the system's capacity to handle legitimate requests becomes compromised.
The operational impact of CVE-2020-13273 extends beyond simple service disruption to potentially compromise the entire GitLab instance's availability and stability. Organizations running affected versions face the risk of complete system unavailability where legitimate users cannot access repositories, perform operations, or utilize the platform's core functionalities. The resource exhaustion can manifest as memory allocation failures, process starvation, or complete system crashes depending on the scale and sophistication of the attack. This vulnerability directly impacts GitLab's core operational integrity and can result in significant business disruption, particularly for organizations that rely heavily on continuous access to their version control systems and collaborative development environments.
Mitigation strategies for CVE-2020-13273 require immediate patching of affected GitLab installations to versions that contain the necessary security fixes. Organizations should implement rate limiting mechanisms and input validation controls to prevent abuse of the vulnerable processing paths. Network-level protections such as intrusion detection systems and application firewalls can provide additional layers of defense by monitoring for unusual resource consumption patterns and blocking suspicious requests. The implementation of proper resource quotas and monitoring systems helps detect when the application begins to consume excessive resources. Security teams should also conduct regular vulnerability assessments and penetration testing to identify similar weaknesses in their GitLab deployments. This vulnerability aligns with ATT&CK technique T1499.004 which covers Network Denial of Service attacks, and organizations should consider implementing the mitigations recommended in the NIST Cybersecurity Framework to address resource exhaustion threats effectively.