Authenticated code execution via unsandboxed Jinja templates
Published Jun 23, 2025 · Updated Jun 23, 2025
Server-side template injection in PySpur 0.1.0 through 0.1.18 allows remote authenticated users to execute code through crafted workflows. SingleLLMCallNode passes its user-controlled user_message configuration directly to Jinja2 Template.render, exposing Python objects and built-ins without a sandbox. Low-privileged API access to create, update, and run a workflow is sufficient, and successful exploitation executes commands with the PySpur server process's privileges.
Summary
What happened
Server-side template injection in PySpur 0.1.0 through 0.1.18 allows remote authenticated users to execute code through crafted workflows. SingleLLMCallNode passes its user-controlled user_message configuration directly to Jinja2 Template.render, exposing Python objects and built-ins without a sandbox. Low-privileged API access to create, update, and run a workflow is sufficient, and successful exploitation executes commands with the PySpur server process's privileges.
The record
- CVE
- CVE-2025-6518
- Published
- Jun 23, 2025
- Updated
- Jun 23, 2025
- Vendor
- PySpur-Dev
- Product
- PySpur
- Classifications
- CWE-791, CWE-1336, T1190
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 23, 2025CVE publishedPublication date reported by the CVE source.
- Jun 23, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0.1.0
- Affected versionversion=0.1.1
- Affected versionversion=0.1.10
- Affected versionversion=0.1.11
- Affected versionversion=0.1.12
- Affected versionversion=0.1.13
- Affected versionversion=0.1.14
- Affected versionversion=0.1.15
- Affected versionversion=0.1.16
- Affected versionversion=0.1.17
- Affected versionversion=0.1.18
- Affected versionversion=0.1.2
- Affected versionversion=0.1.3
- Affected versionversion=0.1.4
- Affected versionversion=0.1.5
- Affected versionversion=0.1.6
- Affected versionversion=0.1.7
- Affected versionversion=0.1.8
- Affected versionversion=0.1.9
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- PySpur Jinja2 reverse-shell proof of conceptfunctional · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
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