Cyber Resilience

CVE-2026-31864

Fit2Cloud Jumpserver ≤ 3.10.22

Published
13 March 2026
Modified
18 March 2026
Patch / advisory
View advisory
CVSS Score v3.1 6.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0035 28th percentile
Risk Priority 50 floored blend · peak EPSS

Summary

CVE-2026-31864 is a medium-severity Improper Neutralization of Special Elements Used in a Template Engine (CWE-1336) vulnerability in Fit2Cloud Jumpserver. Its CVSS base score is 6.8 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Template Injection (T1221); ranked at the 28th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

JumpServer is an open source bastion host and an operation and maintenance security audit system. a Server-Side Template Injection (SSTI) vulnerability exists in JumpServer's Applet and VirtualApp upload functionality. This vulnerability can only be exploited by users with administrative privileges…

more

(Application Applet Management or Virtual Application Management permissions). Attackers can exploit this vulnerability to execute arbitrary code within the JumpServer Core container. The vulnerability arises from unsafe use of Jinja2 template rendering when processing user-uploaded YAML configuration files. When a user uploads an Applet or VirtualApp ZIP package, the manifest.yml file is rendered through Jinja2 without sandbox restrictions, allowing template injection attacks.

CWE(s)
CWE-1336

Related Threats

MITRE ATT&CK Enterprise Techniques

T1221 Template Injection Stealth
Adversaries may create or modify references in user document templates to conceal malicious code or force authentication attempts.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-43651Same product: Fit2Cloud Jumpserver
CVE-2023-43650Same product: Fit2Cloud Jumpserver
CVE-2023-42820Same product: Fit2Cloud Jumpserver
CVE-2023-46138Same product: Fit2Cloud Jumpserver
CVE-2025-27095Same product: Fit2Cloud Jumpserver
CVE-2023-43652Same product: Fit2Cloud Jumpserver
CVE-2024-29201Same product: Fit2Cloud Jumpserver
CVE-2023-42819Same product: Fit2Cloud Jumpserver
CVE-2024-29024Same product: Fit2Cloud Jumpserver
CVE-2023-48193Same product: Fit2Cloud Jumpserver

Affected Assets

fit2cloud
jumpserver
≤ 3.10.22 · 4.0.0 — 4.10.16

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.3.2
  • V1.3.7
  • V1.3.10

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and static analysis can discover missing neutralization of template directives.

SI-10 Information Input Validation good match

Input validation rejects or sanitizes untrusted data before it reaches the template engine, stopping injection of special syntax.

SA-8 Security and Privacy Engineering Principles partial match

Security engineering principles require use of safe templating APIs and proper escaping of external input.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require proper input neutralization in template engines to prevent injection.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can detect template-injection flaws but does not itself implement neutralization controls.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates input validation and sanitization that directly prevents template-injection weaknesses.

A.8.26 Application security requirements partial match
prevents

Application security requirements explicitly call for neutralizing special elements in template engines.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles reduce the likelihood of unsafe template processing but do not prescribe specific neutralization techniques.

A.8.28 Secure coding partial match
prevents

Secure coding standards require proper escaping or sandboxing of template directives, directly mitigating CWE-1336.

References