CVE-2026-55830 | RestrictedPython is a tool that helps to define a subset of … | CVSS 8.3 HIGH

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.

Metadata

CVE ID: CVE-2026-55830
State: PUBLISHED
Assigner: GitHub_M
Reserved: 2026-06-17 16:29 UTC
Published: 2026-07-08 21:16 UTC
Last updated: 2026-07-09 13:46 UTC
Primary CWE: CWE-184
CWE-184: Incomplete List of Disallowed Inputs
Vendor / Product: zopefoundation / RestrictedPython
Sources: cve.org · NVD

Severity & Metrics

8.3 HIGH CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:L

SSVC — CISA Coordinator

Exploitation: PoC
Automatable: no
Tech. Impact: total

Affected products (1)

Vendor	Product	Platform	Versions
zopefoundation	RestrictedPython	—	< 8.3

Weakness (CWE)

CWE	Source	Description
CWE-184	cna	CWE-184: Incomplete List of Disallowed Inputs

CVSS scores (1)

Score	Severity	Version	Source	Vector
8.3	HIGH	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:L

References (2)

https://github.com/zopefoundation/RestrictedPython/security/advisories/GHSA-ffg3-p8fm-mjx2 https://github.com/zopefoundation/RestrictedPython/security/advisories/GHSA-ffg3-p8fm-mjx2
https://github.com/zopefoundation/RestrictedPython/commit/3737596ec9f28c34a073cc845bd2f4c0a80cb671 https://github.com/zopefoundation/RestrictedPython/commit/3737596ec9f28c34a073cc845bd2f4c0a80cb671