CVE-2026-61536 (GCVE-0-2026-61536)
Vulnerability from cvelistv5
Published
2026-07-30 16:50
Modified
2026-07-31 23:01
CWE
  • CWE-94 - Improper Control of Generation of Code ('Code Injection')
  • CWE-470 - Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection')
Summary
Banks generates meaningful LLM prompts using a simple template language. In versions prior to 2.4.3, banks parses Tool JSON objects from the rendered body of {% completion %} blocks and later resolves their import_path field through importlib.import_module(...) + getattr(...) to obtain the callable that handles a tool call. There is no allowlist or sanitization on import_path, so any importable Python attribute (e.g. os.system, subprocess.getoutput) can be selected. When the LLM emits a tool_calls entry whose function.name matches the attacker-supplied tool name, the resolved callable is invoked with kwargs decoded from tool_call.function.arguments, yielding arbitrary code execution in the banks-hosting process. This is distinct from GHSA-gphh-9q3h-jgpp / CVE-2026-44209. That advisory was fixed in 2.4.2 by switching src/banks/env.py from Environment to SandboxedEnvironment. The fix does not touch src/banks/extensions/completion.py, and the unsafe import + getattr chain still executes on 2.4.2. The malicious Tool JSON is plain text in the rendered template body — it requires no Jinja attribute access, so the sandbox is irrelevant. This issue has been fixed in version 2.4.3.
Impacted products
Vendor Product Version
masci banks Version: < 2.4.3
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Show details on NVD website


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