fsspec: Server-Side Template Injection in ReferenceFileSystem leads to Remote Code Execution
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
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| fsspec | filesystem_spec | affected |
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Github GHSA |
GHSA-27vj-qcqg-25rc | fsspec: Server-Side Template Injection in ReferenceFileSystem leads to Remote Code Execution |
No CVSS v4.0
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.475% probability within 30 days)
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ssvc
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Fsspec
Fsspec filesystem Spec |
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Fsspec
Fsspec filesystem Spec |
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threat_severity
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threat_severity
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| 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. | |
| Title | fsspec: Server-Side Template Injection in ReferenceFileSystem leads to Remote Code Execution | |
| Weaknesses | CWE-1336 CWE-94 |
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cvssV3_1
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