CVE-2026-31864
JumpServer has a Server-Side Template Injection Leading to RCE via YAML Rendering
CVE-2026-31864 is a medium vulnerability (CVSS 6.8) in Fit2cloud Jumpserver, published March 13, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 0.41%, the 36th percentile. No source names a fixed version.
- Severity
- 6.8 MediumCVSS 3.1, CVE List
- Exploit chance
- 0.41%EPSS, 36th percentile
- Exploitation
- None known1 public exploit
- Fixed in
- No fix listedNo source names one
Description
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 (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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- High
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| PoC in GitHub | federiconbaez/cortex9-jumpserver-yaml-jinja-sandbox-model | 2026-11-09 |
What each source reports
CVE List Score used
JumpServer has a Server-Side Template Injection Leading to RCE via YAML Rendering
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 (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.
- Record
CVE-2026-31864- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-1336
- Updated
- 2026-11-02
EUVDEUVD-2026-12085
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 (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.
- Record
EUVD-2026-12085- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
NVD
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 (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.
- Record
CVE-2026-31864- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-1336
- Updated
- 2026-11-02
OSV
JumpServer has a Server-Side Template Injection Leading to RCE via YAML Rendering
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 (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.
- Record
CVE-2026-31864- CVSS 3.1
- 6.8 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-1336
- Updated
- 2026-11-10
History
| Recorded | Changed | Sources |
|---|---|---|
| exploits, facts | PoC in GitHub | |
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.