CVE-2026-55830
RestrictedPython guard hooks can be shadowed via positional-only arguments
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Description
RestrictedPython is a tool that helps to define a subset of the Python language which allows to provide a program input into a trusted environment. Prior to 8.3, check_function_argument_names() rejected protected guard hook names for regular, variadic, and keyword-only arguments but omitted positional-only arguments, allowing __getattr__, _getitem_, _write_, or _print_ to be shadowed by a local parameter and bypass the embedding application's access policy. This issue is fixed in version 8.3.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Remediation
No guide yetNo remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.
References (2)
SSVC — Action Prioritization
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CVSS
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- HIGH
- User Interaction
- REQUIRED
- Scope
- CHANGED
- Confidentiality
- HIGH
- Integrity
- HIGH
- Availability
- LOW
Quick Info
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