CVE-2026-55830
RestrictedPython guard hooks can be shadowed via positional-only arguments
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.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:HPrivileges RequiredHigh
UI:RUser InteractionRequired
Scope
S:CScopeChanged
Impact
C:HConfidentialityHigh
I:HIntegrityHigh
A:LAvailabilityLow
Weaknesses
Affected Products
zopefoundation
oss-projectaka accesscontrol, zope, restrictedpython
Exploitability
No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.
References
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