CISA Adds Critical IBM Langflow, Apache Tomcat, and N-able Flaws to KEV Catalog

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) added three critical vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog between August 4 and 5, 2026. This designation confirms that these flaws are being actively leveraged by attackers in the wild, necessitating immediate patching for all affected organizations.

The most severe addition is CVE-2026-9198, affecting IBM Langflow versions 1.0.0 through 1.10.0. This vulnerability allows unauthenticated attackers to achieve full remote code execution (RCE) by chaining two specific API endpoints: /api/v1/auto_login and /api/v1/validate/code. According to analysis from Suriq.io, the flaw essentially left the "key in a bowl by the door," allowing strangers to gain administrative access.

Other critical additions include an authentication bypass in N-able N-central (CVE-2026-18577), which emerged following an incomplete fix for a previous vulnerability, CVE-2026-18556. Additionally, CISA flagged CVE-2026-34486 in Apache Tomcat, a flaw involving the missing encryption of sensitive data that enables attackers to bypass the EncryptInterceptor.

The AI Attack Surface

Langflow is an open-source tool designed for the visual construction of AI agents and retrieval workflows. Because the platform executes code on the server to manage these complex flows, it possesses an inherently high attack surface. The current RCE is particularly dangerous because it exploits a default "auto-login" feature that grants superuser tokens to any requester, bypassing previous security measures.

Industry Implications

For users of Langflow, this vulnerability is catastrophic, as it allows for a complete takeover of the host system. The inclusion of these three flaws in the KEV catalog transforms them from theoretical risks into active threats. The urgency is underscored by the fact that any internet-facing instance of these services is currently at high risk of immediate compromise.

Next Steps for Administrators

Organizations utilizing IBM Langflow, N-able N-central, or Apache Tomcat should prioritize updating to the latest patched versions immediately. Security teams are advised to audit their internet-facing assets for these specific versions and monitor for unusual activity associated with the identified API endpoints in Langflow. While the severity of the Langflow flaw is confirmed by multiple security sources, administrators should continue to monitor official NVD records for final CVSS scoring and enrichment.