Vulnerabilities

CVE-2026-49869 is a critical (CVSS 3.1: 10.0) authentication bypass in the open-source Kestra event-driven orchestration platform: the AuthenticationFilter exempts the public configuration endpoint from Basic Auth using a suffix match (request paths ending in "/configs") rather than an exact path comparison. As a result, an unauthenticated remote attacker can call any API URL whose final path segment is "configs", which is enough to create and execute arbitrary workflows without credentials. Because Kestra ships with script execution plugins (plugin-script-shell, plugin-script-python, etc.) enabled by default, this directly yields unauthenticated remote code execution as root inside the Kestra worker container. All Kestra OSS deployments prior to 1.0.45 and 1.3.21 are affected, with the greatest risk for instances whose API is reachable from the internet or untrusted networks. The flaw is being actively exploited: CISA added it to the KEV catalog on 2026-09-02 (EPSS 1.9%, percentile 79), and headlines covering the KEV batch report attackers deploying reverse shells and crypto miners.

Do: Upgrade to Kestra 1.0.45 (for the 1.0.x line) or 1.3.21 (for the 1.3.x line), or later releases that incorporate the fix. If immediate patching is not possible, restrict network access to the Kestra API (firewall/ACL or a reverse proxy that enforces authentication for all paths, including any ending in /configs). Given active exploitation, audit instances for signs of compromise such as unexplained workflows, reverse shells, or cryptomining processes in worker containers; federal agencies must patch per CISA BOD 26-04 timelines.