CVE-2026-19014 in Consul
Summary
by MITRE • 08/07/2026
Consul Community Edition and Consul Enterprise 1.17.0 through 2.0.2 are vulnerable to an uncontrolled resource consumption issue in the Connect authorization endpoint that may allow a caller to grow the agent's intention-match cache without bound, defeating the operator's cache-disable configuration. This vulnerability, CVE-2026-190124, is fixed in Consul 2.0.3 and Consul Enterprise 1.21.17, 1.22.11, and 2.0.3.
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Analysis
by VulDB Data Team • 08/07/2026
The vulnerability identified as CVE-2026-190124 represents a critical resource exhaustion flaw within HashiCorp Consul's Connect authorization mechanism that affects both community and enterprise editions across specific version ranges. This issue resides in the Connect authorization endpoint where an attacker can manipulate the agent's intention-match cache through crafted requests, leading to unbounded memory consumption that bypasses configured cache limitations.
The technical implementation of this vulnerability exploits a design flaw in how Consul processes authorization requests for service communication within its Connect mesh. When legitimate or malicious actors submit authorization requests to the Connect endpoint, the system fails to properly validate or limit the number of entries added to the intention-match cache. This cache serves as an optimization mechanism to store previously evaluated authorization decisions, but without proper bounds enforcement, it becomes susceptible to abuse through repeated requests that continuously expand its size.
From an operational impact perspective, this vulnerability creates a significant risk for Consul deployments where attackers can consume system resources indefinitely, potentially leading to denial of service conditions that affect the entire service mesh. The flaw particularly undermines operator-defined security configurations that intend to limit cache growth, effectively neutralizing administrative controls over resource consumption. This behavior violates the principle of least privilege and can result in cascading failures throughout the service mesh infrastructure.
The vulnerability manifests as an uncontrolled resource consumption issue classified under CWE-400, which specifically addresses improper resource exhaustion conditions in software systems. The attack vector aligns with techniques described in ATT&CK matrix under T1499.004 for network denial of service and T1566.002 for phishing through social engineering, as attackers can exploit this weakness to disrupt service availability. The flaw particularly affects environments where Consul Connect is deployed with high traffic volumes or where security policies rely on cache-based performance optimizations.
Mitigation strategies should prioritize immediate deployment of patched versions including Consul 2.0.3 and enterprise versions 1.21.17, 1.22.11, and 2.0.3 as recommended by HashiCorp. Operators should also implement monitoring for unusual cache growth patterns and establish stricter rate limiting controls at the network level to prevent abuse of the authorization endpoint. Additionally, administrators should review and validate existing cache configuration parameters to ensure they properly enforce resource limits even in the presence of malformed requests that could trigger this vulnerability.