CVE-2026-104126: JumpServer: Ansible Automation Template Rendering Allows Unsafe Lookup Plugin Invocation

Vulnerability summary

CVE-2026-104126 is a medium (CVSS 6.0) Improper Control of Generation of Code vulnerability in jumpserver. EPSS estimates a 0.38% chance of exploitation in the next 30 days, higher than 31.7% of scored vulnerabilities.

Timeline

1. 13-10-2026
   PublishedVulnerability first disclosed.
2. 16-10-2026
   Last modifiedVulnerability information updated.

Description

JumpServer is an open source bastion host and an operation and maintenance security audit system. Prior to 4.10.17-lts, JumpServer's Ansible-based automation rendering can evaluate attacker-controlled template expressions from users who have permission to create or execute affected automation tasks. Crafted content can invoke sensitive Ansible lookup behavior, including file, pipe, env, and password lookups, within the Ansible execution context, which can disclose files or environment values and may permit limited command execution under the privileges of the automation process. The issue does not provide unauthenticated access or direct access to unrelated JumpServer assets. This issue is fixed in version 4.10.17-lts.

• CWE-94Improper Control of Generation of CodeThe product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.