CVE-2026-104126 — JumpServer: Ansible Automation Template Rendering Allows Unsafe Lookup Plugin Invocation
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.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.4% (30-day exploitation probability)+5
- Technical severity (medium)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Jumpserver Jumpserver).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes matching the vulnerability class (injection), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Jumpserver | Jumpserver | version < 4.10.17 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 6.0 | CVSS 3.1 | Medium | 1.2 | 4.7 | security-advisories@github.com via NIST National Vulnerability Database |
| 6.0 | CVSS 3.1 | Medium | — | — | GitHub_M via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:L/A:L (score shown at the top: security-advisories@github.com) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 14, 2026 → Oct 15, 2026 · 2 reading(s) · max 0.38%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Look for parameters with command/query metacharacters and unexpected child processes of the service.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · jumpserver/jumpserver
- Record published
- CVSS changed · 6.0
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
4 on the record
Elsewhere on this site
Related CVEs (same products)
- Medium CVE-2026-44845 JumpServer: Remote Command Execution (RCE) via Jinja Template Injection in Applet Host Deployment Aug 17, 2026
- Medium CVE-2026-44846 JumpServer: Privilege Overwrite via Organization Invite Logic Flaw Aug 17, 2026
- Medium CVE-2026-54336 JumpServer: KoKo Web Terminal SFTP Path Traversal on Authorized Asset Aug 17, 2026
- Medium CVE-2026-31864 JumpServer has a Server-Side Template Injection Leading to RCE via YAML Rendering Mar 13, 2026
- Medium CVE-2026-31798 JumpServer Improper Certificate Validation in Custom SMS API Client Mar 13, 2026
- Medium CVE-2025-58044 JumpServer has an Open Redirect Vulnerability Dec 1, 2025
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-104126 is "JumpServer: Ansible Automation Template Rendering Allows Unsafe Lookup Plugin Invocation", rated Medium. It affects Jumpserver (Jumpserver); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.0 describes technical severity. EPSS 0.38% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
Comments
Moderated technical discussion. Read the community guidelines.
No comments yet.
Sign in or create an account to comment and suggest corrections.