CVE-2023-1297 in Consul
Summary
by MITRE • 06/03/2023
Consul and Consul Enterprise's cluster peering implementation contained a flaw whereby a peer cluster with service of the same name as a local service could corrupt Consul state, resulting in denial of service. This vulnerability was resolved in Consul 1.14.5, and 1.15.3
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 06/29/2023
The vulnerability identified as CVE-2023-1297 affects HashiCorp Consul and Consul Enterprise clustering implementations, specifically targeting the cluster peering functionality. This flaw represents a critical state corruption issue that can lead to complete service disruption within distributed systems leveraging Consul for service discovery and configuration management. The vulnerability stems from inadequate validation mechanisms within the peering subsystem that fails to properly handle service name conflicts between local and remote clusters. When a peer cluster attempts to establish a service with a name identical to an existing local service, the system's internal state management becomes compromised, creating conditions that can cascade into broader system instability and denial of service scenarios. The flaw exists at the core of Consul's distributed state synchronization mechanisms, where peer cluster communications are not properly isolated from local service definitions.
The technical implementation of this vulnerability manifests through inconsistent state handling during cluster peering operations where service registration and conflict resolution logic fails to properly distinguish between local and remote service identifiers. This issue falls under CWE-362, which addresses concurrent execution using shared data without proper synchronization, and specifically relates to improper handling of service name conflicts in distributed systems. The flaw operates by allowing a malicious or misconfigured peer cluster to inject conflicting service definitions that overwrite or corrupt the local service registry, leading to inconsistent state representation across the cluster. This vulnerability is particularly dangerous because it can be exploited through legitimate cluster peering operations, making it difficult to detect and prevent through traditional network monitoring approaches.
From an operational impact perspective, this vulnerability creates a significant risk to service availability and system reliability in production environments relying on Consul for service discovery. When exploited, the corruption of Consul state can result in cascading failures where dependent services become unavailable, service mesh functionality breaks down, and the entire distributed system experiences denial of service conditions. The impact extends beyond immediate service disruption to include potential data inconsistency issues that may require manual intervention to resolve. Organizations using Consul for critical infrastructure components face heightened risk of extended outages and service degradation, particularly in complex multi-cluster deployments where peering relationships are common. The vulnerability affects both Consul and Consul Enterprise editions, indicating a fundamental flaw in the core peering implementation that requires immediate attention from system administrators.
Mitigation strategies for CVE-2023-1297 involve immediate deployment of patched versions 1.14.5 and 1.15.3, which contain the necessary fixes to properly handle service name conflicts during peering operations. Organizations should implement comprehensive monitoring of cluster peering activities and service registration events to detect anomalous behavior that may indicate exploitation attempts. Network segmentation and access control measures should be strengthened to limit which clusters can establish peering relationships, reducing the attack surface for potential exploitation. The remediation process should include thorough validation of existing peering configurations to identify and resolve any existing naming conflicts before applying patches. Security teams should also implement proactive service discovery monitoring that tracks service registration patterns and alerts on unusual service name collisions. Additionally, organizations should conduct thorough testing of patched environments to ensure that the vulnerability has been properly addressed without introducing new compatibility issues in their service mesh deployments. This vulnerability aligns with ATT&CK technique T1566.002 for credential access through service account manipulation and T1499.004 for endpoint detection and response failures in distributed systems.