CVE-2026-23881

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{}

{"analysis": {"en": {"generated_at": "2026-04-18T02:08:43.733912+00:00", "value": {"mitigation_remediation": ["Upgrade Kyverno to version 1.16.3 or later, or upgrade to 1.15.3 if using that branch, to apply the memory-consumption fix.", "Restrict policy-creation permissions to a minimal set of trusted users or service accounts so that an attacker cannot craft malicious policies until the patch is applied.", "Configure Kubernetes resource limits and monitoring for the Kyverno deployment to detect and contain excessive memory usage, reducing the impact of a denial-of-service event."], "summary": {"action": "Apply Patch", "impact": "Denial of Service"}, "threat_synthesis": {"affected_systems": "The vulnerability affects Kyverno versions prior to 1.16.3 and 1.15.3. The affected vendor is Kyverno, product Kyverno, any installation that uses the vulnerable policy engine component.", "description_and_impact": "Kyverno is a cloud-native policy engine whose policy engine can consume unbounded memory when evaluating policies that use context variables to exponentially amplify string data. This flaw, identified as a resource-consumption vulnerability (CWE-770), enables a privileged user who can create policies to cause the host running Kyverno to run out of memory and become unresponsive, resulting in a denial of service. The impact is limited to the system where Kyverno runs, but the high memory consumption can affect other containers and services on the same node.", "risk_and_exploitability": "The CVSS score is 7.7, indicating a high severity, while the EPSS score is below one percent, suggesting a low probability of exploitation in the wild. The vulnerability is not listed in the KEV catalog, meaning no confirmed public exploits are available. Attackers need policy-creation privileges, which are typically held by administrators or service accounts; therefore, the attack vector is internal or privileged. The primary risk is a DoS of the Kyverno service and potentially other workloads sharing the node if memory is exhausted. Prompt patching reduces the attack surface, and limiting privileges further mitigates risk."}}}}, "created": "2026-01-27T20:16:24.340964+00:00", "updated": "2026-04-18T02:15:05.888732+00:00", "vendors": ["kyverno", "kyverno$PRODUCT$kyverno"]}