CVE-2018-1779 in API Connect
Summary
by MITRE
IBM API Connect 2018.1 through 2018.3.7 could allow an unauthenticated attacker to cause a denial of service due to not setting limits on JSON payload size. IBM X-Force ID: 148802.
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Analysis
by VulDB Data Team • 06/11/2023
This vulnerability affects IBM API Connect versions 2018.1 through 2018.3.7, representing a critical denial of service weakness that could be exploited by unauthenticated attackers. The flaw stems from insufficient validation mechanisms within the API gateway's JSON payload processing capabilities, specifically the absence of configurable limits on incoming JSON payload sizes. This design oversight creates a condition where malicious actors can submit excessively large JSON documents to the system, potentially overwhelming memory resources and causing the API gateway to become unresponsive or crash entirely.
The technical implementation of this vulnerability demonstrates a classic resource exhaustion attack pattern where the system fails to enforce proper input validation boundaries. According to CWE-400, this represents a vulnerability in resource management where the application does not properly limit the size of data structures that can be processed, leading to potential denial of service conditions. The vulnerability allows attackers to manipulate the JSON parser's memory allocation behavior, as the system lacks mechanisms to constrain the maximum size of JSON payloads that can be accepted and processed. This weakness directly impacts the availability aspect of the security triad by enabling attackers to disrupt legitimate service operations through resource consumption attacks.
From an operational perspective, this vulnerability poses significant risks to organizations relying on IBM API Connect for their API management infrastructure. The unauthenticated nature of the attack means that any external party can potentially exploit this weakness without requiring valid credentials or prior access to the system. This makes it particularly dangerous in environments where API gateways are exposed to public networks or untrusted client populations. The impact extends beyond simple service disruption to potentially affecting business continuity, as API gateways typically serve as critical infrastructure components for enterprise applications and microservices architectures. The vulnerability could be exploited in conjunction with other attack vectors to create more sophisticated denial of service scenarios that might persist across multiple service endpoints.
Organizations should implement immediate mitigations including configuring explicit JSON payload size limits within their API gateway configurations, deploying rate limiting controls to prevent excessive request volume, and implementing monitoring solutions to detect unusual patterns of payload size consumption. The recommended approach aligns with ATT&CK technique T1499.004 for resource exhaustion attacks, where defensive measures focus on limiting resource consumption through proper input validation and access controls. Additionally, organizations should consider implementing API gateway-specific security controls that enforce maximum payload size thresholds, utilize automated scaling mechanisms to handle unexpected load spikes, and establish comprehensive logging and alerting systems to detect potential exploitation attempts. Regular security assessments and vulnerability scanning should be conducted to ensure that similar weaknesses are not present in other components of the API management infrastructure.