CVE-2026-49093: Kibana SSRF Vulnerability Bypasses Connector Allowlist

Technical summary

The vulnerability exists in how Kibana validates outbound requests initiated through connector configurations. An authenticated user holding connector management privileges can bypass the allowlist mechanism by crafting specific connector payloads that trigger Server-Side Request Forgery behavior. The flaw resides in CWE-918 (Server-Side Request Forgery) and allows the Kibana server process to issue HTTP requests to destinations that the operator explicitly blocked via egress controls. The CVSS 3.1 score of 6.3 (Medium severity) reflects the authentication and privilege requirement, combined with high confidentiality impact and cross-boundary scope—an attacker can potentially exfiltrate data or probe internal services not directly accessible to end users.

Business impact

Organizations using Kibana for observability and alerting may face data exfiltration risks if their connector allowlists are bypassed. Sensitive internal services, databases, or metadata endpoints could be probed or accessed by a privileged-but-malicious user or compromised admin account. The impact is primarily confidential—no data modification or service disruption is expected—but the breach of intended network segmentation violates security posture assumptions. For organizations with strict egress policies (DMZ deployments, air-gapped environments, or regulated industries), this vulnerability represents a meaningful control gap.

Affected systems

Elastic Kibana is affected. The vulnerability requires the attacker to hold connector management privileges, so impact is limited to environments where such permissions are granted. Organizations using Kibana for alerting, integrations with external systems, or webhook-based workflows are most at risk, particularly if those connectors are configured with sensitive destinations or if connector admin roles are held by multiple users.

Exploitability

Exploitability is moderate. The vulnerability requires authentication and connector management privileges—a non-trivial barrier that rules out unauthenticated or low-privilege attackers. However, within Kibana deployments, connector administrators, platform engineers, or a compromised high-privilege account could execute this attack without additional user interaction. The attack surface is bounded by the access control model; organizations limiting connector management to a small, trusted group reduce risk materially.

Remediation

Apply the security patch provided by Elastic for Kibana. Verify the patch version against Elastic's advisory to confirm the fix is included. In parallel, audit connector management role assignments and ensure least-privilege access. Review existing connector configurations for suspicious or overly-broad destinations. Consider implementing network-layer egress controls independent of Kibana's allowlist as defense-in-depth; egress firewall rules should enforce the intended destinations regardless of what a Kibana user attempts.

Patch guidance

Consult Elastic's official security advisory for the specific patched version of Kibana that addresses CVE-2026-49093. Apply patches to all Kibana instances in your environment, prioritizing those in production and those with externally-reachable connector integrations. Test patches in a staging environment first to ensure compatibility with your connector configurations and dependent services. After patching, re-validate your allowlist rules to confirm they function as expected.

Detection guidance

Monitor Kibana's request logs and connector audit trails for unusual outbound requests, particularly those to internal IP ranges, private cloud metadata endpoints, or destinations not explicitly whitelisted. Look for connector configuration changes made by unexpected users or at odd times. If your organization has network telemetry, correlate Kibana process egress traffic with your intended allowlist to identify bypassed connections. Check Kibana logs for connector execution errors that might indicate failed SSRF attempts. Review access logs for new connector management role assignments or privilege escalations.

Why prioritize this

This vulnerability merits prompt attention for organizations using Kibana connectors, but is not a critical emergency. The requirement for authentication and connector management privileges significantly narrows the attack surface compared to unauthenticated RCE flaws. However, the ability to bypass egress controls—a deliberate security design—elevates priority in environments with strict network segmentation or sensitive internal services. Organizations in regulated industries or with air-gapped deployments should prioritize higher. Those where connector management is tightly restricted can deprioritize slightly, but should still patch promptly within a normal maintenance window.

Risk score, explained

The CVSS 3.1 score of 6.3 (Medium) reflects several factors. Authentication and high access control requirements (PR:L) reduce severity versus unauthenticated flaws. High confidentiality impact (C:H) reflects the ability to breach network segmentation and access blocked resources. No integrity or availability impact moderates the score. The cross-boundary scope (S:C) accounts for the ability to access resources outside the Kibana application's direct trust boundary. The high Attack Complexity (AC:H) suggests the exploit requires specific preconditions or knowledge of the allowlist mechanism.

Frequently asked questions