CyberRota Analysis
AI-GeneratedThe fsspec library versions from 0.9.0 to 2026.6.0 are vulnerable to arbitrary code execution due to unrestricted Jinja2 template rendering in the processing of Kerchunk reference JSON documents. Attackers can exploit this vulnerability by supplying malicious documents, potentially leading to the execution of Python code when the reference filesystem is accessed. Organizations using affected versions of fsspec, particularly those leveraging xarray or similar data processing tools, should prioritize upgrading to version 2026.6.0 to mitigate this risk.
Public Exploit Signal
A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.
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Original NVD Description
fsspec is a specification and Python implementation framework for filesystem interfaces. From 0.9.0 until 2026.6.0, fsspec.implementations.reference.ReferenceFileSystem evaluates fields from Kerchunk reference JSON documents through unrestricted jinja2.Template(...).render(...) calls in _process_references1._render_jinja, _process_templates, and _process_gen in fsspec/implementations/reference.py. A document supplied inline or fetched from an attacker-controlled URL can provide template expressions that execute Python code when the reference filesystem is opened, including through consumers such as xarray, before referenced data is read. The _process_gen path is reached whenever a document includes a gen array, while the other paths depend on template-related options and values. This issue is fixed in version 2026.6.0.